Chapter 2

At The Crime Scene

Place a suspect at the scene

Can be used to reconstruct the sequence of events

Might provide the modus operandi, motive for the crime (MO)

Why are crime scenes valuable?

First Job = Save lives

Detain suspects

Protect the crime scene

Detain witnesses

Role of First Responder

NotesDate and timeLocationWeather and/or environmental conditionsDescription of crimeLocations of evidence relative to key pointsNames of all people involved (including

authorized personnel, witnesses, and victims)All changes that have occurred during the

investigation

Documenting the Scene

Before anything is touched, the scene needs to be photographed!

Points of entry and exitClose up images of the victims and evidence

(from different angles)Use a ruler for scale when appropriateImages from the perspective and view of

witnessesNo Photoshop or editing allowed!

Photography at the Crime Scene

Becoming more and more commonWalk through the crime scene and narrate

while no one else is present.Show entries and exitsLocations of evidence, victims, and weaponsCannot be edited in any wayLink to CBSNews footage

Videography at the Crime Scene

Gives an accurate layout of the crime scene

Everything must be to scale

Includes victims, weapons, evidence, reference points

Can never be tampered with or changed

Sketching the Crime Scene

Fragile evidence collected first (fingerprints, blood stains

Wet items need to be dried to prevent mold/mildew

Everything needs to be sealed tightly to prevent leaks/contamination

Typical containers include pill bottles, glass vials, manila envelopes and plastic bags

Collecting and Packaging Evidence

Firearms need to be placed rigidly into a wooden box or gun case

Chemical must be collected and stored in glass containers

Biological items need to be kept refrigerated to avoid degradation

Controls need to be collected whenever possible (including blood and hair samples)

Collecting and Packaging Evidence

Written record of who has had possession of the evidence at all times.

It can NEVER be broken!

Maintaining the Chain of Custody