fs ch 2

Chapter 2

Securing and Searching the Crime Scene

Forensic ScienceRichard Saferstein

© 2009 Pearson Education, Upper Saddle River, NJ 07458.

All Rights Reserved.2

Arrival at the Crime SceneFirst arriving officer:

1. Medical assistance for injured victims

2. Detain suspects/witnesses

3. Secure the crime scene

4. Call for any additional personnel




Securing the Crime Scene

Establish appropriate boundaries

Secured area should include actual crime scene and locations of evidence




Post officers to restrict access

Crime scene log

Investigators should never alter the crime scene

Securing the Crime Scene




Walkthrough (initial survey)

1) Points of entry/exit 2) Indirect path to the center of the crime

scene3) Evidence located and documented.4) Scene conditions observed and

recorded.

Surveying the Crime Scene




Primary Crime Scene-location of initial crime

Secondary Crime Scene-location after the initial crime occurred

-inferred by the presence or absence of specific evidence.

Surveying the Crime Scene




1) Staging area outside crime scene.2) Lead investigator assigns tasks. 3) Equipment stored. 4) Investigators discuss aspects of the

crime scene.5) Investigators communicate with

personnel at other crime scenes.6) Central area of communication.

COMMAND CENTER




Thorough and systematic. Search pattern depends on the

size/locale and the number of collectors

Do not overlook pertinent evidence. Physical evidence: -everything -anything

CRIME SCENE SEARCH




Line/Strip Search Pattern-Start at the boundary of the crime scene and search in straight lines across to the other side.

-Best for outdoor/large areas/large groups

Grid Search Pattern- search area divided into grids

-best for large areas/plane crashes

Searching the Crime Scene




Spiral Search Pattern-Boundary inwards in a circular pattern

Quadrant/Zone Search Pattern-Divided into zones

-Each zone searched/then zones switched -Best for indoors/smaller areas

Searching the Crime Scene




Lead investigator:-decides when all evidence is

recorded/collected Final survey:-review the scene/collect all evidence

and equipment.-scene released to the proper

authorities

Departing the Crime Scene




Crime sceneExamine this scene closely:

-wheelchair

-signs of forced entry?

-blood?

-your initial conclusions?




Securing the crime sceneActual crime sceneEnthusiasm can be

dangerous!

-note the crime scene tape around the upper floors

-Rookies!




Crime sceneHow many people

should you let into the crime scene?

-This look a little crowded

-No coordination of tasks

-Milling about approach to crime scene




Caylee Anderson’s crime scene

This is an outdoor scene in a wooded location that had flooded since the PR had first called 911.

-aerial view




Caylee

This is an example of a wooded crime scene with soft dirt and large amounts of natural artifacts




CayleeThe area where the

skeletal remains were found is clearly evident.




You decideHere you have an elderly

male in bed covered with blood. The first police officers determined it to be suspicious.

What do you think?What do you see in the

picture?See the blood? See the tissues on the

nightstand?Never assume!!!




You DecideAnother view: Lots of

blood.-What color is the blood?

-What can you determine from this color?

-What does the pooling of the blood tell you?




You DecideThis is the bathroom:-Note the blood drops

on the floor-There is blood on the

toilet-More tissues on the

bureau

Give up?




You DecideThis was a natural death. There were no open woundsThe tissues indicated the decedent had tried to

control the bleedingThe color of the blood and the smell in the

residence (you can’t smell it of course) were indicators of an upper gastrointestinal (GI) bleed.

A GI bleed is when someone is bleeding internally and eventually the blood gets thrown up and it can be very messy and appear like a homicide.

fs ch 2

Travel

crime scene search

crime scene evidence

wooded crime scene

crime scene tape

primary crime scene

caylee andersons crime

outdoor scene

scene conditions