Crime Scene

Processing the Crime Scene

Processing the Crime Scene

“Physical evidence encompasses any and all objects that can establish that a crime has been committed or can provide a link between a crime and its victim or a crime and its perpetrator.”

Secure and Isolate the Crime Scene

Responsibility?

Secure and Isolate Con’t

Once the scene is secured, lead investigator establishes:

Record the Scene

Since the crime scene will not remain in its original state for very long, a permanent record of the scene must be made as soon as possible. These records are also required at trial.

Record the Scene

The three methods of recording the scene are done in the following manner:

Record Scene: Photography

Photography the scene should be

photographed in an unaltered condition. Unless someone is injured, everything should be left in its original condition until all evidence is photographed.

Record Scene: Photography

What should be photographed?

Record Scene: Photography

What should be photographed? Con’t

Record Scene: Photography

Close-up Photos of Physical Evidence with a ruler or something else to show size/scale (point of reference)

Videotaping/digital cameras can also enhance the preservation of the evidence in its original state

Still photography is still the best for its detail

Record Scene: Rough Sketches

after photos, the investigator will sketch the scene (see diagram)

Record Scene: Rough Sketch

Why?

Rough Sketch Con’t

All objects are measured from two fixed points ( ) accurately with a tape measure (NOT GUESS)

Each object is then given a letter and a legend or list will correlate the letter to the item

The sketch should always designate North

Rough Sketch Con’t

Record Scene: Finished Sketch

A finished sketch will be made from the rough sketch and will then be drawn to scale using the measurements provided in the rough sketch. (This is what will be used as evidence in court.)

Record Scene: Notes Note taking is a constant activity throughout

the processing of the crime scene and include: Detailed written description of the

scene with the location of physical evidence recovered

Must identify the time the evidence was discovered, by whom, how and by whom it was packaged and marked and disposition of the item after it was collected

Tape recording notes is a helpful tool, but at some point the tape must be transcribed

Searching the Scene

Types of Searches (See Diagram) – searches at the crime scene must be systematic and the type of search will be determined by locale and size of the area and actions of victim and suspect at the scene

Searching the Scene

Searching Con’t

The physical evidence that should be collected include hairs, fibers, blood, glass, soil, fabric impressions (in a car or on furniture)

Particular attention is paid to cross-transfer of evidence between the perpetrator and the weapon and/or victim

Clothing from the suspect may be collected and must be bagged separately

Areas of the crime scene may be vacuumed and the sweeping submitted to the lab for testing

Vacuum Equipment

Searching Con’t The following items obtained from the body

should be sent to the lab for testing:

Collect and Package Physical Evidence

Physical evidence must be collected in such a way that prevents any change between the crime scene and the crime lab Hairs, blood and fibers should not be

removed at the scene. The article it is on should be sent to the lab intact and the evidence removed there.

Collect and Package Con’t

Blood stains can be removed by either scraping and transferring to a moistened swab or cutting out the stain

EACH DIFFERENT ITEM MUST BE PACKAGED SEPARATELY!!!

Many materials can be used to package evidence – plastic pill bottles, manila envelopes, and vials etc.

Collect and Package Con’t

Blood (and all clothing) SHOULD NEVER be packaged in an air-tight plastic container Why?

Any charred debris SHOULD be packaged in an air-tight container Why?

Maintaining a Chain of Custody

Continuity of possession (chain of custody) must be established whenever evidence will be presented in court

EVERY PERSON WHO HANDLED THE EVIDENCE MUST BE ACCOUNTED FOR!!!!

Evidence is carefully packaged and marked at the crime scene (collector’s initials, date of collection, location of evidence)

Chain of Custody Con’t

Whenever a transfer of evidence occurs it must be recorded

Chain of custody should be kept to a minimum

Obtain Controls

When possible, any collected evidence (hair, fibers, soil, etc.) should be compared with a control (known sample) from the actual crime scene

Bloodstain evidence must be accompanied by whole blood or buccal swab controls which are obtained from all relevant crime scene participants

Submitting Evidence to the Lab

Evidence submission forms are required for all articles to be tested

Case history should accompany the evidence submission form so the analyst can examine the evidence in a logical sequence

The particular type of test should be noted, but analyst is not bound only to that test

Submitting Evidence Con’t

Each item for testing must be listed, packaged separately and assigned a number or letter

Crime Scene Safety – (see guidelines)

See text pgs 47 - 50

Legal Considerations at the Crime Scene

Any evidence at the scene must be removed in compliance with 4th Amendment privileges.

Allowances for a warrant-less search:

Legal Allowances Con’t

Mincey v. Arizona

under the pretext of buying drugs, police forced entry into Rufus Mincey’s apartment and an undercover officer was killed

over a 4 day period police gathered evidence without a warrant

Mincey was convicted but appealed saying the evidence was collected without a warrant or his consent

Mincey v. Arizona Con’t

Michigan v. Tyler

a fire burned down Tyler and his partner’s business

police were prevented from immediately searching the scene due to smoke, darkness, etc.

the next morning evidence was collected and removed

Michigan v. Tyler Con’t

4, 7, and 25 days later more evidence was collected without a warrant and was used to convict Tyler and his partner of arson

The Supreme Court says….

Court Case Conclusion

The Moral of the Story: OBTAIN A SEARCH WARRANT BEFORE

INVESTIGATING AND COLLECTING PHYSICAL EVIDENCE!!!!!