The Crime Scene

Locard’s Exchange Principle Every contact leaves a trace! Whenever two objects come together they must affect each other in some way. Something is likely to be exchanged between them! Physical Evidence - anything that establishes a link between a crime and a person

Principle of Individuality Two objects may be indistinguishable, but no two objects are ever identical. Things can be put into classes or even individualized in useful ways.

Frye vs. Daubert Daubert - “Does it work?”; Frye - “Do scientists like and use it?” FRE 702 - If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education, may testify thereto in the form of an opinion or otherwise, if (1) the testimony is based sufficiently upon facts or data, (2) the testimony is the product of reliable principles and methods, and (3) the witness has applied the principles and methods reliably to the facts of the case.

Search and Seizure Evidence at a Crime Scene 4th Ammendment to the Constitution “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.”

Search and Seizure Evidence at a Crime Scene 4th Ammendment to the Constitution “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.”

Search and Seizure 4th Ammendment to the Constitution Allowances for Warrantless searches: the existence of an emergency. The need to prevent the immediate destruction of evidence. A search of a person or property within the immediate control of the person provided it is made incident to a lawful arrest. A search made by consent of the person involved.

Collection of Evidence - Legal Precedent MINCEY v. ARIZONA (U.S. Supreme Court, 1978) Drug bust that went wrong and an undercover police officer was killed. Police spent 4 days searching and seizing evidence Mincey arrested and convicted. Supreme Court ruled evidence collected was inadmissible because it was not from a proper search and seizure. Evidence taken without proper authority is probably not legally admissible.

Collection of Evidence - Legal Precedent Michigan v. Tyler (U.S. Supreme Court, 1978) Building destroyed by fire was put out in early AM. Building left unsecured until 8 AM when a preliminary search was done (for cause of fire). Subsequent searches (at 4, 7, and 25 days) removed additional evidence. Tyler convicted of arson. Supreme Court: “…entry to fight a fire requires no warrant, and that once in the building, officials may remain there for a reasonable time to investigate the cause of the blaze. Thereafter, additional entries to investigate the cause of the fire must be made pursuant to the warrant procedures”

Physical Evidence Must be recognized at crime scene. What relates to the crime and what doesn’t. Must be properly collected, preserved and controlled - from massive to microscopic Only aids in investigations (evidence doesn’t solve crimes by itself) www.crime-scene-investigator.net

Steps Taken at a Crime Scene Secure and Isolate the scene. Render medical help and arrest suspects (if needed) Preserve and protect evidence (isolate area) Exclude unauthorized personnel Designate Officer in Charge (with authority) Establish boundaries Document site Collection of Evidence

Evidence Team Personnel Duties and Responsibilities Team Leader Photographer and Photographic Log Recorder Sketch Preparer Evidence Recorder/Evidence Recovery Personnel Specialists

Evidence Team Personnel Duties and Responsibilities Team Leader Assume control and access Determine search pattern and assignments Coordinate with groups involved Continuously evaluate work Release crime scene

Evidence Team Personnel Duties and Responsibilities Photographer and Photographic Log Recorder Photograph entire scene (before and after entered) Photograph victim, crowd, vehicles Photograph evidence before it’s moved (including fingerprints, casts, etc.) Photograph evidence both in wide view (position at scene) and close-up (with scale) Possible use of video recording (does not replace still photography Prepare photographic log

Capture Crime Scene

Wide angle lenses are used to distort the truth or emphasis it

Details preserved

Evidence Team Personnel Duties and Responsibilities Sketch Preparer Diagram area of scene (incl. orientation) Rough sketch - accurate dimensions, orientation and location of evidence (from a fixed point) Finished sketch - aesthetic appearance (usually done later sometime w/ CAD) Set forth major items of evidence on sketch (with scale) Make measurements (double check)

Evidence Team Personnel Duties and Responsibilities Sketch Preparer Rough Sketch

Evidence Team Personnel Duties and Responsibilities Sketch Preparer Finished Sketches

Evidence Team Personnel Duties and Responsibilities Sketch Preparer

Evidence Team Personnel Duties and Responsibilities Evidence Recorder/Evidence Recovery Personnel Have evidence photographed/sketched before collection Describe evidence and location on container Package evidence Maintain chain of custody and evidence log Ensure proper safety of collection (e.g., infectious materials)

Evidence Team Personnel Duties and Responsibilities Specialists May include: Anthropologist Blood expert Bomb technicin Criminalist Engineer Entomologist Medical examiner Odontologist Surveyor Etc.

Crime Scene Searches Thorough and Systematic Unbiased and not overlook any relevant evidence Depends upon locale, area, type of crime and conditions

Crime Scene Searches Typical search patterns Outer to inner Saferstein “Criminalistics”

Collecting Evidence

Cast’s of Physical Evidence Blood Spatter Analysis

What determines the type and manner of collecting and preserving physical evidence? The nature of the evidence

Q. What type of evidence is to be retrieved from a deceased victim for examination in the crime laboratory? Clothing Fingernail scrapings Head and pubic hairs “Orifice” swabs Bullets Hand swabs for gunshot residues

Packaging Evidence Prevents any change after collection Proper identification Prevents cross contamination (separate packaging) Preserved intact (e.g., blood on clothes) Crime scene safety

Q. Who is responsible for the integrity of handling the evidence? Chain of Custody: is a list of all persons who came in possession of an item of evidence. Initials and date should be recorded

Chapter 2 Physical Evidence Legal Precedent Evidence Team Crime Scene Searches Evidence Collection and Packaging Chain of Custody