hurst report

7/30/2019 hurst report

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Gerald L. HurstConsulting Chemist Fires and Explosions

September 26, 2008

ANALYSIS OF THE FIRE ORIGIN AND CAUSEEVIDENCE IN TEXAS V EDWARD GRAF

Fire Incident Synopsis

On August 26, 1986 at about 4:40 PM, Mr. Edward Graf arrived at his home in Hewitt,

Texas with his sons, Joby (9) and Jason (8.). Approximately 15 minutes later, smoke and

flames were seen issuing from a storage shed in the back yard of the residence. When thefire department arrived at about 5:00 PM, the shed was fully involved in fire.

After extinguishing the fire, firefighters found the charred bodies of the two boys in the

back of the shed.

The local fire department fire marshal, acting more out of compassion than reason,

arranged with his fellow firemen to remove all the fire debris to a pit in the local dump onthe evening of the fire.

Within a few days of the fire, the family and friends of Grafs wife began a campaign toinfluence the District Attorney to prosecute Mr. Graf. The joint effort was led by Mrs.

Grafs sister-in-law, Del Gerdes, who prepared an 8-1/2 page voluntary statement for the

Prosecutor following consultation with family members and friends. Carol Schaefer, Mrs.

Grafs long-time friend, joined Mrs. Gerdes in the effort to persuade the District Attorney

by furnishing 6 pages of notes casting suspicion on Mr. Graf.

On September 3, the local authorities called the Texas State Fire Marshals Office torequest a fire investigation. Deputy State Fire Marshal Porter arrived in Hewitt on

September 4, to discuss the case. The fire scene had been completely obliterated long

before that time. The Fire Marshal was only able to view the fire debris in a jumbled pilefrom the edge of an inaccessible pit, where it had been mixed with other materials.

Prior to the trial in 1988, the prosecution hired a private expert from New York, Mr.King. Mr. King and Fire Marshal Porter undertook to determine the origin and cause of

the fire based solely on a limited number of essentially amateur photographs of the post-

fire debris. The term solely is applied here because both of these investigators stressedthat their conclusions were reached without factoring in eyewitness testimony lest itintroduce bias into their interpretation of what they believed was infallible fire pattern

evidence.


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The Shed Door Bolt Issue

The only physical fire investigation was conducted during a half-hour period in the late

afternoon of the fire by volunteer firefighters Lucenay (Assistant Fire Chief), Clark (Fire

Marshal), Robertson and Howard.

The investigators found two slide bolts or latches associated with the double four footwide doors of the shed, one in the open position and one in the closed (locked) position.

In determining the bolt positions, Lucenay operated the bolt mechanisms:

Lucenay SOF 36A. We sifted through the Christmas decorations, and we looked

by the doors or the major part of the--most burned part

of the fire was. Right by one of the front doors there was

a slide latch, kind of like a bolt lock. One was in the

locked position.Q. Now, how could you tell, sir, it was in a locked position?

A. When you the pull the slide latch up and move it back, the

discoloration of the latch itself showed that it was in the

locked position.

Q. Okay.

A. There was another one a couple of feet from it that was in

the open position. And we could tell the same way. When

you pushed it up and closed it or locked that one, the

discoloration showed it was in the open position due to the

heat.

Lucenay and Clark took photographs of the shed area which include the bolts appearing

as tiny objects occupying about 1/5,000 of the area of the pictures (States Exhibits 60,

61). State Fire Marshal Porter, who was unaware of Lucenays physical examination ofthe bolts, would later testify in elaborate detail that he could ascertain from the poor-

quality photographs that both bolts were in the locked position. He used this erroneous

conclusion to convince the court that the children had been deliberately locked in the

double-door shed after the ignition of the fire.

The shed door latch issue was a lynch pin in the States case for arson/murder. If one or

more exterior bolts on the left-hand door could be shown to have been in the closedposition during the fire, it would follow that that the children had been locked in the shed

after the fire began. In order to prove this theory, State Fire Marshal Porter relied solely

on the two pictures introduced as States Exhibits 60 and 61, from which he claimed to beable to ascertain the position of the bolt mechanisms during the fire. Mr. Porter had such

unquestioning faith in his ability to read fire patterns from even distant photographs that

he had adopted a protocol in which he abstained from the study of any eye-witnessreports or statements which might influence his judgment.


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Porter SOF 937A. My job as an arson investigator requires me to eliminate

all possible accidental fire sources prior to making any

kind of decisions Therefore I must enter every fire that

I go to with the idea that it's an accidental fire, and Icannot be influenced by any outside information.

Q. Cannot be influenced by what?

A. Any outside information.

Q. And what will be considered outside information, witness

statements and things?

A. Witness statements, accusations from people, rumors. It

makes my job more difficult when all of that stuff is

thrown in.

Because of Mr. Porters inadvisable protocol of ignoring eyewitness evidence, he did not

know that States Exhibit 61 was a photograph which had been taken by Lucenay andClark of a bolt which Lucenay had previously inspected by manipulating the slidemechanism and had determined first hand that the bolt was in the unlocked position

during the fire. The Lucenay photo, which is identifiable as such by the automatic date

signature, shows that the lock is free of ashes and debris and was therefore handledbefore the photo was taken.

Mr. Porter believed he had established logically inescapable evidence that the left door

had been locked during the fire:

Porter SOF 993

Since it's my opinion that both of these latches were in

the locked position at the time that the fire occurred,

and my discussions with Mr. Graf at his home I was told

that there were two latches on the outside of the door and

one on the inside, at least one of those two latches had

to be mounted on the exterior surface of the door and had

to be in the locked position at the time of the fire.

Porters reasoning was wrong because it was based on the false premise that both of the

pictured latches were in the closed position and also because it relied on the assumption

that there were no other latches in the structure other than the three he had listed.

Porters deduction at trial that the shed door was bolted was based on the false premise

that the total number of door bolts was three. He had apparently failed to review his ownfire investigation report prior to going to trial some two years after the investigation. In

that report, he recorded the number of bolts as four, two on the outside and two on the

inside:


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Porter Fire Investigation Report, September 18, 1986, page 1, paragraph 3

(Emphasis mine)

The only point of entry into the structure was at the southwest corner of the

shed, where two four-foot wide doors were located on the south wall. These

doors were wood-framed and covered by the same material (masonitesheet-siding) as the remainder of the structure. The doorway could be locked

in three locations from the outside. Two slide-bolts were located on the

exterior sides of the doors. One approximately two feet above ground level

and the second approximately seven feet above ground level. The third lock

was a ring-and-hasp lock, located at a level of approximately five feet above

the ground. The door on the left, facing the doors, could also be locked

inside into the closed position by vertically placed slide bolts at the top

and bottom of that door. No other points of entry or exit were present on the

structure, as there were no windows.

Compounding his errors, Porter got the positions of the inside and outside bolts of thetwo doors transposed to some extent in both the Report and in his trial testimony. Giventhat the left door was the normal entry, the two inside latches would have followed the

standard pattern and been located on the inside of the right hand door with the exterior

bolts being mounted on the left hand door

At trial, the Prosecutor pointed out part of the error in Porters testimony regarding the

positioning of the exterior bolts.

Porter SOF 983

A. All latches on the right front door from our conversation were on

the exterior of the shed.

Q. And this is what you understood from Mr. Graf?

A. Yes, sir .

Q. So we're talking about three slide bolt locks?

A. Yes, sir. That's all I was made aware of.

Q. From your examination of State's Exhibit 58 are you able to

see the location, approximate location of the locks ?

A. I can see the exterior locks.

Q. Okay.

A. In this photograph I can see that there is a slide lock

near the top of the door here, a ring and hasp lock in the

center, and another slide lock down here near the base.

Q. Okay. Now, assume if you would -- and I am showing State's

Exhibit 58. Assume If you would, sir, that you

misunderstood Mr. Graf or were misinformed.

Graf did not misinform Porter. It was Graf who gave Porter Exhibit 58, which clearlyshows the two slide bolts on the exterior of the left door. Mr. Porter did not do his

homework on the bolt issue in preparation for trial.


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Without any implication of reliance on statements by the Defendant, it is still worthnoting that he testified that there were 5 interior bolts associated with the right hand door.

Two of these latches retained a removable center stud against which the two doors

closed. It appears unlikely that the Defendant would have lied about a matter which

would have made him readily subject to impeachment by information the Prosecutorcould readily have obtained from Mrs. Graf, who was cooperating with the prosecution.

The Defendants testimony about the number of latches present on the right door was notchallenged by the prosecution.

Whether there were five interior latches as stated by the Defendant or two as written byPorter in his report or only one as stated by Porter at trial, it is evident that the extensive

testimony of Fire Marshal Porter regarding the alleged proof that the left door was bolted

from the outside was devoid of merit. Only one bolt was found in the closed position and

at least one closed bolt would have been present under any scenario whether the left doorwas open or not.

The Left Shed Door Position Issue

The prosecution theory that the victims were locked in the shed at the beginning of the

fire required that that both doors be closed during the fire. Fire Marshal Porter appliedthe same photographic metal color-analysis technique to the left door hinges which had

failed him with regard to the door bolt of States Exhibit 61. In this portion of his

analysis he reasoned that the left door must have been closed during the fire because the

hinge pin areas of the lower two left hinge did not appear to him to be discolored withrespect to the wing areas.

Porter SOF 974

Okay. When I went back to look at the hinge area on this

photograph, I noticed that the hinge in both sections, the

top or the bottom and the middle, which I am only looking

at two of the three hinges on the door, I noticed that they

appear to be very evenly affected by the heat. In other

words, there is not any abnormal discoloration in one area

that's not located in an other part of the hinge. Based on

that, 1was able to realize that if a door is in the open

position, then the hinge pin area is going to be an exposed

area to more heat than the wing area that is mounted on the

exterior surface of the wood.

Porters reasoning is absurd for two very sound and very obvious reasons:

1. The photograph is overexposed with respect to the hinges and numerous other

metal objects such as the various metal structures, including the lawnmowers andbed frames components in the same view. This overexposure results in loss of

contrast, making smooth surfaces appear to be featureless. In the referenced


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picture, one also immediately notes false hues of the black charcoal, which

appears to range from white to gray to black depending on the angle of theimpinging light. The white charcoal is an illusion caused by reflected light. In

order to photograph a fire scene, it is necessary to increase the exposure to

prevent the char patterns from appearing as solid black areas with no detail. The

photographs show excellent detail in the charred areas, which means that all lightareas will appear as a washed out beige color. In order to photograph the hinges

properly, the photographer would have had to reset the exposure to a lower leveland moved much closer to the target hinges.

2. The hinge pins may have been exposed to heat at an earlier time in the fire thanwere the wing areas, but as the fire progressed, both the wings and hinge pin areas

were bathed in wood flames. This fact is obvious because both hinges are

mounted on wooden members which have been heavily charred by flames. Any

color contrast which may have been present during the early fire stages wouldhave been annihilated by the later total exposure to fire.

A much better approach to the question of whether the door was closed or open is toemploy elementary fire dynamics and fire chemistry.

The experts in this case gave estimates of the amount of alleged flammable liquid pouredon the floor ranging from about 2 quarts to two gallons:

Prosecution Closing Argument SOF 2052

But we do know from our experts that a

flammable liquid was used, from their experts that two

gallons of flammable liquid was used. Charlie King

would say it was a large quantity, more than a couple,

three quarts. He didn't want to pin it down how large.

Their expert said two gallons.

Now where did the gas come from? This gas

can, this is a new one but the one that this

represents, was sitting right here, see? And the

expert testimony is that it had gasoline in it. ..

It is undisputed that there was no explosion associated with the ignition of the fire, that is,

there was no explosive damage to the structure or noise produced until later in the fire

when several aerosol cans exploded with loud reports but no consequential mechanicaleffect on the structure.

If we assume that the prosecution theory of the fire is correct, the hypothetical perpetratorpoured a quantity of flammable liquid on the floor of the shed, ignited it and closed the

door.

For purposes of analysis, assume that the quantity of flammable liquid was less than half

of the lowest expert estimate or approximately 1.25 liters (= 1.3 quarts, weighing 0.93 kg)


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of gasoline or other flammable liquid. The 12X16 foot shed would contain about 50 kg

of air prior to ignition. At the then ambient temperature gasoline reacts completely withair in the weight ratio of approximately 15.5 parts air to one part gasoline. Shortly after

ignition, that is, within a few tens of seconds, the spilled gasoline would react with

0.93*15.5/50*100 = 29% of the air in the shed, which is to say that it would remove 29%

of the oxygen in the structure.

The air remaining in the shed would have a maximum average concentration of oxygenreduced from its initial 23% by weight to (1-0.29)*23 = 16%. The residual oxygen

concentration would actually be much lower than 16% because of the thermal expansion

of air out of the shed and also the contribution of other burning materials to the removalof oxygen in the first minute.

Once the initial, brief surge of rapid burning was over, the fire would either smother for

lack of sufficient oxygen or continue to burn or smolder at an extremely slow rate for avery prolonged period of time. A drop in oxygen concentration from the atmospheric

value of 23% to 16% has an enormously disproportionate effect on the rate of burning ofall common materials. The principle fuel in the shed was cellulosic materials such as theMasonite walls, plywood flooring, exposed studs and rafters, cardboard boxes and the

like. The effect of reduced oxygen concentration on the rate of burning of such materials

is shown in Figure 1, which depicts experimental data from the Society of FirePrevention Engineering Handbook, Second Edition:

Figure 1


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It should be noted that at 16.7% oxygen, the cellulosic fuel sputters out after releasing

only a tiny fraction of its potential fire energy.

Once the oxygen has been rapidly scavenged from a structure such as the shed by a

flammable liquid a process requiring less than 60 seconds continued burning of the

less flammable contents depends on air leakage and must proceed at a very low rate. Inorder to enter the full involvement stage which characterized the shed fire, it is highly

unlikely that such an anemic fire could have burned the very large opening in the wallstructure which would have been necessary to provide sufficient ventilation for full

involvement in the short time frame of the subject fire.

The above description of the effects of flammable liquids in inhibiting fire growth

through oxygen starvation in closed rooms has been verified by full scale burn tests. The

following relevant 10th

conclusion was excerpted from the report of an extensive research

program conducted in 1997, USFA Fire Burn Pattern Tests, FA 178, 7/97, page 67:

10. The use of a volatile ignitable liquid, such as gasoline, as an accelerant willcause rapid consumption of the oxygen in a room. Depending on the available

ventilation this may deplete the oxygen in the room, reduce the heat release rate

of the fire, and prevent flashover. In this situation, patterns indicative of the

accelerant use were easily recognized and residue of the accelerant could still be

smelled.

If the left door of the shed was open when the fire began, the opening would have been

sufficient to allow the building to reach full involvement well within the available timeframe and support an ongoing fire fueled by indigenous materials. This observation is

supported by a large body of data from experimental fires which has established the

mathematical relationship between ventilations parameters and full involvement, alsoknown as post-flashover burning. This area of fire technology was not understood by fire

investigators prior to about 1991 and became slowly introduced into the field over the

following decade.

The oxygen starvation of structure fires is frequently encountered in house fires which

may go undetected until days after the occurrence of the fire if the initial fire fails to

break a window and thereby furnish the necessary oxygen to begin the process of growthto full involvement. The shed had no windows and thus was not subject to this

mechanism which requires that the ventilation hole extend vertically to allow the ingress

of fresh air through the bottom portion of the vent and the simultaneous egress of hotgases from top portion.

The obvious conclusion is that the door was open from the beginning of the fireregardless of the nature of initial material ignited.


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Auguring with Charcoal

The field of fire investigation has always been plagued by what are often termed old

wives tales relating to supposed principles which can be applied to determine the origin

and cause of fires. Three of the most common myths relate to the appearance of thecharcoal blisters or alligatoring which is formed when wood chars. These false

principles hold that:

1. Fires caused by flammable liquids burn hotter than wood and therefore cause

large charcoal blisters.

2. Flammable liquid fires produce shiny blisters whereas normal fires produce

matte or dull blisters.

3. The direction in which a fire progresses can be determined by the orientation of

the cracks between the charcoal blisters. Upward burning or normal firesproduce horizontal cracks whereas downward burning or abnormal fires causedby flammable liquids create vertical cracks.

There is no basis for any of these three myths. Experiments involving the charring ofwood have repeatedly shown that the size and luster of charcoal blisters are not

determined by the nature of the burning fuel or the direction of fire. The major cracks

between blisters occur at 90 degrees to the grain of the wood. Thus wooden studs in

which the grain is perpendicular exhibit horizontal cracks. Floor joists have a horizontalgrain orientation and thus exhibit vertical cracks.

In the present case, the State Fire Marshal, Porter, delivered long treatises to the juryinvoking each of the above myths repeatedly in his testimony. Porter used the crack

orientation and blister size to prove that the fire had burned both upward at high

temperature and downward into the floor joists and therefore allegedly involved aflammable liquid on the floor. The use of the myths was so frequent that it is impractical

to quote each instance. Typical examples are cited below, including the contribution of

the Prosecutions consultant, King.

Porter Fire Investigation Report, page 3, paragraph 3:

This process began by an examination of the degree and type of charring that was

present near the area of origin. This examination revealed that the charring to the

beams below the flooring was very heavy. The "ALLIGATOR" pattern in this area

was observed to be deep seated and divided into large patch sections. This pattern

is commonly associated with an intense, fast burning fire.

Porter Fire Investigation Report, page 3, paragraph 4:

Indications of a fast burning and intense fire were not consistent with the fire load

that was present in the area of origin. Appearance of the charring to be glossy is


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indicative of the presence of a liquid hydrocarbon accelerant substance being in

the area of origin.

Porter SOF 952:

Q. And when a fire is burning down, you are telling us that

those lines will be vertical up and down?A. Correct.

Q. Okay.

A. And in a fire that buns from the bottom up, you are going

to have a different pattern in which your main lines of

progression of the alligator patterning, the separation

lines are going to run horizontal .

Q. So what you are telling us, if the fire burns the way it

normally does, up and out in this V shape as you described

earlier, that the deeper lines left are going to be

horizontal?

A. Correct.Q. Is that one of the tools you use in analyzing a fire is to

look at these patterns?

A. Yes, sir .

Q. Is that what you did in this case?

A. Yes, sir. I did.

Porter SOF 955

Q. All right, what about when an accelerant is used? What

does it do?

A Well, the fire is progressing so fast and so hot from one

area to another that it is -- you're actually getting a

much larger square or a much larger patch of alligatoring

in each area.

King SOF 1107

Q. If you could back up just a little so these jurors can see,

and show them the ridges [cracks] on the doorway.

A. This is the piece of wood here that we're looking at, which

is the front entrance doorway, bottom frame of it. And

this enhancement gives you a fairly good idea of how deep

the ridges are, and the intensity and the heavy attack on

the wood. And its burning in a downward direction because

these alligations or these ridges are vertical. So that

was another thing in my mind which convinced me that there

was some type flammable liquid used there.

King SOF 1114

Q.Which way did the ridges run?

A. They ran up and down.


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Q. What does an up and down ridge mean?

A. This burning [1st

first floor hole] was the sane as this burning [2nd

floor hole].Q. What does that mean?

A. So this fire was burning downward, which is flammable liquid.

All of the above opinions are baseless inventions which have been repeatedly disprovedsince the time of the subject trial. The old wives tales on which they are based are

frequently included in published lists of arson myths. See the chapter entitled TheMythology of Arson Investigation in Scientific Protocols in Fire Investigation by John

Lentini, 2006.

NFPA 921, the de facto standard of care in fire investigation, contains the following

strong warnings against reliance on the appearance of char blisters as indicators of thepresence of an accelerant:

6.2.4.3 Appearance of Char. In the past, the appearance of

the char and cracks had been given meaning by the fire investigation

community beyond what has been substantiated by

controlled testing. The presence of large shiny blisters (alligator

char) is not evidence that a liquid accelerant was present

during the fire, or that a fire spread rapidly or burned with

greater intensity. These types of blisters can be found in many

different types of fires. There is no justification for the inference

that the appearance of large, curved blisters is an indicator

of an accelerated fire. Figure 6.2.4.3, showing boards exposed

to the same fire, illustrates the variability of char blister.

6.2.4.3.1 It is sometimes claimed that the surface appearance of

the char, such as dullness, shininess, colors, or appearance underultraviolet light sources, has some relation to the use of a hydrocarbon

accelerant or the rate of fire growth. There is no scientific

evidence that such a correlation exists, and the investigator is

advised not to claim indications of accelerant or a rapid fire

growth rate on the basis of the appearance of the char.

The Holes in the Floor

It appears that everyone involved in this case, including the defense lawyers and the

defense expert were convinced that the large areas burned completely through the floor in

the vicinity of the doorway and a smaller area several feet removed could only have beenthe direct result of a flammable liquid spill burning downward.

The idea that a gasoline puddle on a plywood floor, once ignited, will burn through the

floor sounds plausible to most people who have never tried the process experimentally. It

is an unfortunate fact that for many years a large proportion of rank-and-file investigators

tended to interpret holes burned through floors as evidence of ignitable liquid spills.


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The simple fact is that ignited gasoline spills on plywood do little or no significant

damage to the wood beyond sometimes producing occasional very shallow surface char.The level of damage to the surface is mitigated by the fact that the evaporating flammable

liquid tends to cool the wood under it until it has all evaporated and then the burning

stops. A second mitigating factor is that a typical spill only burns for about 60 seconds,

sending most of the generated heat upward away from the wood. A wooden floor willnot continue to burn once the gasoline is gone and 60 seconds is much to short a time

span to burn through a half inch of wood.

Clearly, from time to time the occasional fire investigator may have tested gasoline on

plywood and noted that there was no burn-through. There must have been somecollective sense among the rest that the matter was not quite as simple as it was being

presented in courts. There arose a theory which seemed to allay the doubts about the

hole-burning abilities of gasoline. The new explanation, which one can still find in the

occasional publication, was that flammable liquids burn downward into wood if they areallowed to soak in for a period before ignition

The soaking liquid theory of hole-burning was no more valid than some of the other oldwives tales in the industry but it had apparent scientific credentials. The first reasonably

scientific textbook in fire investigation was written by Professor Leland Kirk in 1969 as

the First Edition of Kirks Fire Investigation. In this otherwise most excellent book, Kirkdescribed experiments in which he found that some ignitable liquids produce more char

on the surface of wood than do others. He speculated that this might be the result of

some liquids penetrating the wood better than others. This speculation turned out to be

wrong, but it provided a stepping stone to the logical but incorrect extrapolation thatlonger soaking with a given liquid would lead to deeper penetration and thus deeper

charring.

The author of this report has tested the burning properties of wood which has been

soaked in hydrocarbon liquids for 24 hours versus wood freshly wetted with the

accelerants and found that there is no significant difference in the level of charring. Thetwo types of samples were also carefully weighed and no significant difference was

found in the tiny quantity of hydrocarbon liquid absorbed.

In 1988, the two prosecution experts, King and Porter, believed that flammable liquidswhich have been allowed to soak into plywood for a period of time somehow acquire the

ability to burn downward through a half inch of wood. Fire Marshal Porter testified that

the required soaking period was at least a few minutes, whereas Consultant King opinedthat the time required was closer to the 30 to 60 minute range.

Porter SOF 982

Q. So then is your testimony that the pour pattern and the

liquid would have had time -- that we were discussing

earlier, would have had time to soak in?

A. Yes, sir.

Q. And how much time usually is needed for that?


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A. It wouldn't have taken more than a few minutes.

King SOF 1211

Q. Thank you, sir. Now there's been a lot of discussion about the pour patterns both

around the point of origin A and point of origin B, [Note that A and B are holes

in the floor]A.Yes, sir.

Q. Pour patterns created by a flammable liquid.

A. Yes, sir.

Q. Tell the Jury how long does it take for a flammable liquid to soak into a plywood

surface in order to create that kind of patterning once it's ignited?

A. Once it's ignited? I think --

Q. I mean, it would create the pattern only after it's burned, correct?

A. Yes.

Q. My question is how long would the flammable liquid have to stay on the board

before ignition in order to create pour pattern?

A. It would have to soak on the board. The exact time I would not know, but itcouldn't be poured and then immediately ignited because it wouldn't seep down.

Q. Are you talking about a matter of hours or a matter of minutes?

A. It would be very difficult to put parameters on it but it would have to soak for a

while, certainly more than a few minutes in my opinion.

Q. Okay.

A. Because there again, vapor ignites, not the liquid, so the liquid would have to be

a period of time to be absorbed into the floor.

Q. Okay.

A. The exact time I don't know.

Q. Less than an hour, less than thirty minutes?

A. About that. Probably no more, certainly no less.

Kings testimony is another example of the pitfalls of treating fire pattern reading as

some sort of pure science which should not be contaminated by knowledge of eyewitnessobservations. King did not realize that the Defendant had been home less than 30

minutes at the time of the fire.

The testimony of the two prosecution experts about the purported mechanism by whichthe alleged flammable liquid had managed to burn the joists under the floor was

creatively speculative at best. King envisaged a mechanism by which the gasoline

seeped through the porous plywood and somehow attacked the joists despite the lackof ventilation under the floor a clearly impossible phenomenon:

King SOF 114

If there were just something on the plywood section, you

would have some scorching on the plywood and the fire would

burn away. But with flammable liquid it seeps below.


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In this testimony, King is not referring to seepage through wood joints because he is

dealing with large sheets of plywood. Leakage through the few joins present in the roomwould, at most, produce only local charring to joists not the widespread and uniform

general damage observed. This testimony also illustrates the false paradigms in the mind

of the investigator which imbues flammable liquids with almost magical powers to

penetrate wood and burn through surfaces conventional solid fuels can only scorch. Inthis instance King has reversed the actual burning abilities of ordinary solid materials

versus liquid accelerants,

As early as 1969, Professor Kirk conducted experiments with solids and liquids and

found that indigenous materials common in fires could severely char wooden plankswhich flammable liquids could only scorch. An example of his work is shown in figure 2,

which demonstrates that a flaming curtain is much more effective in burning through

wooden flooring than is a highly volatile flammable liquid. The same is true for virtually

all burning solids such as wood and paper products.

Kirks Fire Investigation, 1st Edition, page 216, 1969

Figure 2

This early work should have been a wake-up call for fire investigators who had becomeconvinced that flammable liquids could burn downward through wooden flooring and

tended to underestimate the role played by common household materials, but the mythpersisted and is still encountered occasionally in contemporary cases.

More recent work by various researchers has shown the limitations of downward burning

of flammable liquids on wooden floors as compared with the effects of ordinaryindigenous fuel loads and flaming solid fall down, that is, burning structural materials,


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furniture and household items which collapse on or radiate at floors during the course of

a fire.

The 5th

edition of Kirks Fire Investigation shows graphic illustrations of spilled gasoline

burning on a plywood sheet and the aftermath of the fire (Figures 3.4, 7.18a). The

plywood survives the large fire with almost no surface damage, as contrasted with theeffect of a burning cardboard box containing crumpled newspaper, which produces heavy

charring (Figure 7.18c).

Experiments with burning gasoline on wooden floors were conducted under the auspices

of the National Institute of Justice and published in 2001 as Flammable and Combustible

Liquid Spill Burn Patterns, NIJ Report 604-00. The study showed that quart-sized

gasoline spills on wooden flooring burned for approximately 60 seconds, producing brief,

towering flames but only superficial damage to the wood floor. Gasoline spills were also

tested on carpeting with the result that the fires failed to burn through the fiber backing.

The lesson of these experiments for the subject fire is that indigenous materials wouldhave had the potential to burn holes through the plywood floor which would have beenimpervious to a burning flammable liquid.

In light of the experimental work which has been conducted since the time of the Graffie, it is obvious that the prosecution theory that a flammable liquid burned downward

through the shed floor is untenable.

The Pyrolysis Zone Theory

State Fire Marshal Porter offered extensive testimony claiming that he could differentiate

flammable liquid burn patterns on wood flooring from patterns caused by normalmaterials by the width of the pyrolysis zone at the edge of the pattern. The pyrolysis

zone is the area of partially decomposed and therefore discolored wood always present at

the edge of char patterns.

Porter SOF 954

A Okay, Like I said before, in a slow, normal burning fire

you're going to get a pyrolysis area that's wide , generally

about one and a half times the width of the charring area

or the alligatored area.

In a faster burning fire that area is going to be cut

down, and it will maintain a very close contact with that

area that is charred. Also instead of fading from one

color into the color of the wood, that line is going to be

very distinct . It will almost be like the line you see

here . It will go straight from a dark color to a light

color.

Q In your experience as a fire investigator, what can you

determine from these differences in pyrolysis other than


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whether it was a fast or slow burning fire?

A. I can determine whether or not there was some kind of

accelerant or some kind of product that allowed that

fire to burn more quickly in that area.

Porters testimony is nonsense. The nature of the fire source cannot be determined fromthe width of the pyrolysis zone. Materials indigenous to every household can and do

produce floor fire patterns with very sharp edges and thin pyrolysis zones. An excellentexample is given in figure 3, a photograph excerpted from the 2002 edition of NFPA 921

which shows how perfectly a burning cardboard box can create the illusion of the

presence of a flammable liquid. The burning box produced an excellent pour patternwith an extremely thin pyrolysis zone and damage which greatly exceeded that which

would be produced by a comparable spill of gasoline.

Figure 3. Apparent Pour Pattern from Burning Cardboard Box

Flashover and Full Involvement

When a substantial fuel load such as a piece of furniture burns in a room, the resultingplume of smoky gases from the fire forms a hot layer against the ceiling. The layer

grows thicker as the fire progresses. The smoke particles in the upper layer radiate heat

in all directions, including downward. If the temperature of the smoke layer remains wellbelow about 500 degrees Celsius, the floors, room contents and lower walls may remain

relatively unaffected by the radiation for a prolonged period of time. However, if the fire


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source is powerful enough to raise the temperature of the upper layer to 500-600 Celsius,

all combustible lower-level surfaces exposed to the increased radiation will begin to emitflammable vapors which have the appearance of steam. Subsequently, ignition of the

flammable vapors occurs and flame spreads across the entire room in a matter of seconds

The resulting fire is no longer localized but extends over every exposed combustible

surface in the room. The transition from a localized fire to one in which the entire roomis set aflame is called flashover.

If the room has adequate ventilation from an open door or from windows breaking under

the influence of heat, the fire will continue to burn on a scale which is limited only by the

rate at which fresh air can pour in from the ventilation openings. This stage of a fire isknown as post-flashover burning or full involvement, and it is characterized by

greatly increased temperatures, high radiation and the ability to burn downward through

combustible surfaces such as wooden floors.

At the time of the subject fire, the properties of post-flashover fires were virtually

unknown. Investigators had been trained in the basic mantra that natural fires burn upand out. For decades they had viewed low burn patterns, holes in floors, meltedthreshold plates, spalled concrete floors and other low burn artifacts as indicators of the

presence of flammable liquids. Their beliefs were compounded by a grossly exaggerated

view of supposed differences between normal fuel loads and the imagined power ofliquid accelerants.

Beginning in the 1990s, a series of research projects were undertaken to explore the

behavior and end effects of post-flashover fires. The first important discovery was that iftwo identical rooms are ignited using gasoline as an accelerant in one and no flammable

liquid in the other, there was very little discernible difference in the fire patterns

generated after flashover. Full-involvement burning for even a brief period producesoverwhelming low-level burn patterns which mimic liquid pour patterns. Laboratory

experiments showed that wood flooring subjected to the levels of radiation in full

involvement fires could burn through in a matter of minutes. During the same period,experiments with flammable liquids poured on wooden flooring demonstrated that those

liquids could only superficially char the surfaces.

Prior to the better understanding of flashover, so-called fast fires were usuallyattributed the presence of gasoline. However, as more and more flashover experiments

were conducted, it became apparent that ordinary fuel loads such as chairs, sofas,

cabinetry, trash bags, stacks of cardboard boxes and the like were capable of bringing aroom to flashover within a period of a few minutes.

Today there are readily available videos of test fires in which a single piece of furniture isshown to bring a room to flashover within 3-5 minutes of ignition. For an example of the

rapid rise of a conventional fire to flashover in the absence of flammable liquids see the

National Institute of Science and Technology video at:


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http://www.faberc.org/Library/?action=view&item=item&collectionID=BFRL_M

M&itemID=LivingFlashover

In this video, a sofa ignited by a small flame, brings a living room to flashover in

approximately three minutes.

Once a room has gone through flashover and entered the full-involvement stage, the rate

of burning, the nature of the fire patterns created and the location of maximum damagebecomes more and more independent of the actual area of origin. The areas of maximum

damage are determined by the access of the various fuel loads in the room to oxygen.

This means that heavy damage often occurs in the vicinity of doorways through whichfresh air is drawn in. This area of low-lying damage may progress along the floor,

following the flow of incoming air. The outgoing upper-level fuel-rich gases and

incoming air-rich streams interact along the floor creating a blowtorch effect which can

easily burns holes in the floor and may continue to the back wall opposite the door oreven from room to room, leaving trails which suggest poured liquid accelerant.

The ventilation effects described above have been noted in full-scale burn tests. SeeUSFA Fire Burn Pattern Tests, FA 178 7/97. This extensive work published in 1997

confirms the important points made above. The following excerpts from the conclusions

of this learned treatise are relevant to the current case (emphasis mine):

1. The ventilation of the room of fire origin has a great effect on the growth and

heat release rate of a fire and, for this reason, greatly affects pattern formation.

Patterns which indicated areas of intense burning but were remote from the point

of origin were observed and were determined to be from ventilation effects only.

This was observed in rooms which had flashover conditions where clean burn

areas were produced under windows away from the origin. This was also

observed on walls opposite door openings.

In this case, observations indicated that the fresh air being drawn into the room

through the lower portion of the door mixed with excess fuel and produced a jet

of flame or hot gases which continued to travel across the floor and impact the

wall. At the point of impact of this floor jet, a clean burn pattern was produced

with its base at floor level.

3. The presence of floor patterns in a room which has had flashover conditions is

not a reliable indicator of the presence of an ignitable liquid introduced for

incendiary purposes. It was observed that floor patterns were consistently

produced on different floor surfaces by the pyrolysis and combustion of the floor

surface caused by flashover, with and without the use of an accelerant,

7. When flashover conditions have been produced in a room, patterns which are

located at low levels on the walls as low as the floor may be produced in areas

not related to the origin. These low patterns may be produced by the burning of

furniture items or ventilation effects. Accurate origin determination can not be


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made based solely on the presence of areas of low burning when flashover

conditions existed.

Flashover and the Subject Shed

It is undisputed that the shed was fully involved when the fire department arrived. Evenin the absence of eyewitness evidence, a contemporary fire investigator would recognize

the clear fire pattern indicators which show low widespread low charring in all areaswhich were exposed to the intense effects of post-flashover radiation. The damage

necessarily occurred within a total burning period of less than 30 minutes after ignition

and probably less than 20 minutes. It was this supposedly fast fire growth which ledthe investigators to believe that a flammable liquid had been used as an accelerant. Their

error in believing that the relatively short time period was an abnormal phenomenon was

the result of the lack of knowledge of flashover effects in the 1980s.

The shed was an ideal candidate for flashover. The walls were bare, flammable

pressboard (Masonite) with open studs and the floor was half-inch plywood. Thecontents of the shed included, among many other items, stacks of cardboard boxes, anupholstered chair and a roll-away bed with mattress in the vertical position. The shed had

an internal surface area of about 74 square meters. With the 4 foot-wide left door open,

the heat release rate required to bring the shed to flashover within 5 minutes would havebeen less than two megawatts, a figure well within the potential peak burning rates of the

larger fuel loads, in particular that of the bed or the bed coupled with the adjacent

cardboard boxes and flammable wall surface.

The expected jet of floor-level flame from the doorway (as described in USFA

conclusion 1 above) would be associated with turbulent mixing, very high temperatures

and resulting high local radiation and convection on the plywood floor and later on theunderlying joists. This mechanism operating in conjunction with the already high

background radiation would account for the burning of the joists. The joists would also

be burned on both sides by the embers from the plywood floor. Unlike the joists in thepier and beam construction of a house, the shed joists rested directly on the ground.

Thus, falling embers and firebrands from the plywood floor would remain in contact with

the joists.

All of the alleged indicators of the presence of a flammable liquid cited by the

investigators are readily explained by the natural occurrence of flashover.

The Position of the Bodies

Both Fire Marshal Porter and Consultant King expressed strong opinions that thepositions of the bodies on their backs was highly unusual based on their personal

(anecdotal) experience. They concluded that the two victims must have been rendered

unconscious prior to the fire and placed in the face-up position by the perpetrator.


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Neither of the two investigators was qualified to testify about either the relative rarity of

any given fire-victim body position or the state of consciousness of the victim.

Porter SOF 994

A. Yes, Sir. I was very concerned because both bodies, both

victims in this fire were found lying on their back face upin a rather relaxed posture.

In my experience as a fire investigator and in

studying cases after cases after cases, it's very unusual

to find a victim that is making an effort to protect their

self or making an effort to escape from a fire lying on

their back because their natural positionwhen you stand

up when you fall, you are going to fall to a forward

position; if you're crawling, you're going to fall down

onto your stomach.

Porter SOF 995Q. I take it from your experience you're talking about finding

any fire victim on their back that's conscious; is that

right?

A. Any fire victim that is awake and alert during the fire and

makes any effort to escape, the odds are very, very high

that they will always be found face down. You will very,

very seldom find one face up.

King SOF 1128

This was a view of he child and removed from that area.

My concern was that it's in a almost relaxed position.

Its in a position of acceptance. The children I've seen

in fires you won't find this way. You don't find them on their back.

King SOF 1167A. I think that they were unconscious at the time of the

fire or incapacitated, yes, that is correct-

Q. Do you think sir that that was done accidentally by

something they might have taken in that shed, or are

you trying to tell the Jury that my client did it or

some other person did it?

A. I made no accusation against your client. I would

believe that someone made them incapacitated or

unconscious at the time of the fire, yes, sir, that is

correct.

Both King and Porter made a mistake that was common in the 19th

century in believingthat the relaxed position of the bodies somehow reflected the status of those bodies

before loss of consciousness or death. When a person passes out from smoke inhalation,


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the muscles relax and the limbs fall from whatever position they were in while the person

was still awake. Later, the heat of the fire causes the contraction of the muscles andchanges the attitude of the body. The belief that one can tell what the person was feeling

or how they were reacting prior to loss of consciousness or death has been fostered by the

extensive influence of the Sherlock Holmes novels on many contemporary investigators.

The author conducted a brief random review of a number of reported fire cases across the

country and found numerous fire incident reports in which deceased victims of accidentalfires were found lying on their backs on the floor of the burned structure. The following

excerpt from the learned treatise Advances in Forensic Taphonomy by William D.

Haglund and Marcella H. Sorg, CRC Press, 2001, page 462 describe an especiallyrelevant case in which two boys who died in an accidental fire were found in different

positions, one on his side and one on his back:

The in situ recovery consisted of removing a number of layers of burnt rubble

from atop the two victims. Following exposure of the bodies, a plan view map

was made of the scene, including the position and orientation of the victims andthe associated physical evidence (Fig 23.5). The individual farthest from the

closet door was on his side while the other boy was lying on his back

The boys trachea were soot-filled, providing evidence that the boys were still

alive when the fire began. The lack of perimortem trauma (aside from fire-related

damage) in combination with the contextual reconstruction (including the final

position and orientation of the boys) strongly suggested that the manner of death

was accidental. The boys may have been playing with matches in their room,

and, rather than calling their parents when the fire started, panicked and hid in

the closet.

The investigators claims that they could deduce arson and murder from the fact that the

subject victims were found on their backs is obviously a case of too much inference from

data with no probative value and apparent reliance on fictional forensic science.

Conclusions

1. The investigator, Fire Marshal Porter, erred in concluding that the left shed door wasbolted from the outside. His finding was based on poor-quality photographs and

contradicted the findings of the Assistant Fire Chief who had actually examined the bolts

and made the photographs on which he was relying. He also remembered incorrectly thenumber of bolts present on the double door system and their locations. Even if his

photographic study had been correct, he could not logically have proved the door was

locked.

2. Both investigators King and Porter incorrectly concluded that the doors of the shed

were closed during the fire. If the doors of the shed had been both closed, the fire wouldhave died or proceeded at a rate far too slow to reach full involvement in the observed

time frame. If a flammable liquid had been used to start the fire, it would have


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exacerbated the depletion of oxygen in the windowless shed and the fire would quickly

have sputtered out or been reduced to a trivial or smoldering level without breaching thewalls or doors.

3. The char appearance indicators used by both prosecution investigators have all been

shown to be arson myths by research conducted subsequent to the time of trial. Thesemyths include the luster of the char, the orientation of the char cracks, the size of the char

blisters and the width of the pyrolysis zone at the edges of char patterns and holes. Noneof these so-called indicators have any relationship to the use of a flammable liquid.

4. The Holes in the floor were not caused by a flammable liquid burning downwardthrough the plywood. Flammable liquids do not burn downward through wooden

flooring, but at most only cause light surface charring. The theory that flammable liquids

soak into flooring over time and then are somehow able to burn downward is an old

wives tale. Soaking has little or no effect on the level of char damage.

5. The fact, that the shed was fully involved in fire within a period of less than 30 minuteand that the charring inside the shed appears on all exposed surfaces proves that the shedunderwent flashover.

6. The holes in the floor were a natural consequence of post-flashover burning. A secondcause of holes in the floor was the action of burning indigenous solid materials (fall

down). Burning solids can produce holes in wooden flooring which is impervious to the

action of spilled ignitable liquids.

7. Flashover and the transition to full involvement could reasonably have been expected

to occur within five minutes of ignition of indigenous materials in the shed with a match

or lighter.

8. All of the observations of burn damage as well as the rate of growth of the fire can be

readily explained as normal consequences of a conventional fire involving flashover andsubsequent full involvement.

9. The position of the bodies on their backs is not an unusual occurrence in accidental

fires. The position of the extremities does not reflect their position prior to the loss ofconsciousness or even prior to the actual burning of the bodies. The so-called relaxed

appearance of the bodies does not reflect the attitude of the victims prior to succumbing

to smoke inhalation but is simply a consequence of the natural relaxation of muscletension with loss of consciousness.

10. There is no evidence whatsoever to support the theory that the subject fire involvedthe use of a flammable liquid. In the absence of a positive laboratory analysis for a

flammable liquid, the prosecutions theory for the presence of such a material is nothing

more than speculation. The States arson debris analyst testified to the presence oftoluene and xylene isomers in a sample of fire debris which included a shoe. His

testimony was irrelevant because these substance are not only commonly found in shoes


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but are also generated in ample quantities in most structure fires involving the ubiquitous

plastics, synthetic fabrics, paint, rubber, wood finishes and the like, which were present inabundance in the shed.

11. There is no element of physical evidence in this case which is not generally common

to accidental or child-initiated post-flashover structure fires.

hurst report

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