Chapter 2The Scene of the Crime

Mock Crime Scene- Video Clip

Fundamental Practices at Crime Scenes

Secure and Isolate Crime Scene Record Crime Scene Photograph Crime Scene Sketch Crime Scene Maintain Detailed Notes Conduct Systematic Search for Evidence Collect and Package Evidence Maintain Chain of Custody Obtain Standard/Reference Samples Submit Evidence to Library Maintain Safety at Crime Scene

Securing the Scene Responsibility: 1st officer to arrive (first

responder) Medical assistance provided if needed EVERY person entering scene is a potential

destroyer of evidence (intentionally or accidentally)

Prevent entry by unauthorized personnel› Ropes, tape, barricades

Record maintained of anyone entering/leaving crime scene

Separating the Witness Preventing witnesses from talking.

› Allows for comparison of their accounts › Helps prevent them from working together to

create a story. Ask them questions about the incident such

as:› Where were you when you observed the crime?› What did you see happen?

Record/Scan Crime Scene Lead investigator evaluates the area.

› Limited time for processing scene before it gets disrupted by various personnel

Boundaries of crime scene determined› Primary crime scene› Secondary crime scene

Initial walk-through conducted by lead investigator

Strategy developed to process scene Photograph and/or sketch scene Take detailed notes

Seeing the Scene Photos taken without altering the scene or

moving objects If anything gets moved, photos may not be

admissible in court as evidence. Detailed notes taken to override this issue.

Seeing the Scene ALL angles of crime scene must be photographed All adjacent areas as well All points of entry/exit If scene includes body, pictures of the position and location

relative to entire scene must be taken Close-ups of injuries and weapons Once body is removed, the surface under body must be

photographed Each piece of evidence must be photographed in its

original location next to a ruler or other measuring device AND a number I.D. card

Video recorders are also used, but have not replaced still photographs

Sketching the Scene Once photos are taken, the crime-scene

investigator will complete a rough sketch of the scene.› Rough sketch uses geometric shapes, letters and

numbers.

Finished sketch is created with much more care and detail. › Computer aided drafting (CAD) can be employed

to do this.

Rough Sketch

Finished Sketch – Hand Drawn

Finished Sketch (CAD)

Maintain Detailed Notes

Must be a constant activity Must include a written description of scene

and locations of all objects of all evidence

Searching For Evidence Searches must be conducted with extreme care

and have to be thorough.› Hap-hazard searches clues missed or lost.

Systematic searches, using specific patterns are used.

Critical areas of the scene may vacuumed with portable vacuum cleaners equipped with special filters.

The search for evidence extends beyond crime scene to the autopsy› Medical examiner contributes results of toxicology and

pathology examinations

Systematic Search Patterns

Search patterns include:› Spiral searches (outward & inward)› Quadrant method aka Grid and Zone› Parallel search

Spiral Search

Grid and Zone

Also called the Quadrant Method

Parallel

Securing and Collecting Evidence Evidence must be collected and packaged

correctly so it does not change from the time it was collected to the time it is processed by the crime lab. › Ex: evaporation, contamination, breakage, etc.

Each piece of evidence is packaged separately. Evidence must be handled with forceps

(gloved hands only) or similar tools

Securing and Collecting Evidence

Evidence collecting includes: Plastic pill bottles, manila envelopes, glass

bottles etc.› for storing hair, fibers, glass and various small or

“trace” evidence. Paper- “druggist fold” or bindle

› Way to store trace evidence.

Chain of Custody List must be maintained of all persons who had

possession of a particular item of evidence.› Without it- Authenticity and integrity of the evidence

are in question and it may not be admissible in court. Every time evidence container is opened and

closed it must be sealed with a label containing› examiner’s name, date and location of the item.› If the evidence is moved to another location/lab, the

date of this transfer must also appear on the label. Complete record of all persons in touch with the

evidence is maintained and these persons may be summoned to court to testify.

Reference Samples All evidence must be compared to a known

(standard/reference) sample For example, blood-stained evidence must be

accompanied by blood or buccal samples from both the victim as well as the suspect(s)

Same is true with hair, fibers, soil, etc.

Questions:Use Chapter 2 Pages 56-59 to answer the following

questions:1. Describe the procedures for collecting and

packaging evidence. 2. What is a “druggist fold” (or bindle) used for? 3. Identify all the tools used for evidence collection.4. How are bloodstained materials, charred

materials, and clothing collected and preserved?5. Create a druggist fold using a sheet of paper.

Refer to the worksheet for instructions. Turn this in with your assignment.

Evidence Collection Evidence must be collected and packaged

correctly to prevent change from the time of collection to the time of processing by the crime lab. › Changes- evaporation, contamination, breakage,

etc. Each piece of evidence MUST be packaged

separately. Evidence MUST be handled with forceps

(gloved hands only) or similar tools

Evidence Collection Blood-soaked clothing must NOT be stored in

air-tight containers › trapped moisture may cause the growth of mildew

and mold and destroy the blood.

All clothing MUST be air-dried and individually stored in paper bags.

Charred clothing or debris, MUST be stored in air-tight containers preventing evaporation of petroleum residues.

Questions

1. Why would investigators remove a small paint chip from the vehicle belonging to a suspect of a hit-and-run case?

It can act as a reference sample/standard to be compared to paint recovered at the scene.

Submitting Evidence to the Lab Delivered personally or by mail

› Exceptions to mail delivery: explosive, certain chemicals, live ammunition, etc.

Receiving lab must get a case history or any such report along with the evidence.

Clear request of type of examination for each piece of evidence included.› Analysts may perform other tests if necessary

Include completed Evidence submission form and list of all evidence items.

Mincey vs. Arizona (1978)

**See Module 10 Packet** Supreme Court ruled that law enforcement

officials› May enter in search of victims and provide aid

when needed. Limited to realistic areas (ex: not in a shoebox)

› May search for perpetrator under same guidelines.

Mincey vs. Arizona (1978)

May seize evidence in plain view as they search for victims and perpetrators.

Restrictions: Seized item must easily be determined to be relevant without

examination. Plain view seizures only conducted when evidence may be lost,

destroyed, or altered.

What is the 4th Amendment?

Legal Considerations at Crime Scenes Removal of any person/evidence from crime

scenes must be done in conformity with Fourth Amendment privileges:› The right of the people to be secure in their

persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.

Legal Considerations at Crime Scenes

Search warrants are REQUIRED. A warrantless search can only be conducted under the following circumstances:› Existence of an emergency› To prevent immediate loss or destruction of

evidence› Search of a person or property of the person during

his arrest› Search and seizure with the consent of the persons

involved

O.J. Simpson Use the Crime Museum’s article regarding the

collection and use of evidence in the O.J. Simpson trial to answer the following questions.

1. Identify some of the key pieces of evidence found at the crime scene.

2. Describe why many critical pieces of evidence were not admissible in court. Provide at least three examples from the text to support your answer.

Review Activity: Sketching the Scene

Use Figure 2-3 (Diagram of a crime scene) and your textbook (pg. 48-51), to answer the following questions:1. Identify the important elements of a detailed

rough sketch of a crime scene.2. Differentiate between a rough sketch and a

finished sketch. 3. Do you think it is important to document the

location from which photographs were taken? Explain your answer.