Crime Investigation

What makes a serial killer tick? How do forensic experts solve crimes using cutting-edge technology? Who are the men and women that risk their lives to put criminals behind bars?

These questions and more are related to the subject of Crime Investigation. Real crime, real people, real drama - Crime Investigation is the hard work by the true professionals who work meticulously and methodically to solve the mystery behind the crime – motive, the modus-operendai and men involved in crime! Crime Investigation opens the door to crime labs, police archives and courtrooms, providing a behind-the-scenes look at criminal investigations and probing unexplained mysteries.

Physical Evidence at a Crime Scene

Evidence used to resolve an issue can be split into 2 areas - testimonial evidence and physical evidence. The testimonial evidence would be any witnessed accounts of an incident. The physical evidence would refer to any material items that would be present on the crime scene. These items would be presented in an issue or incident to prove or disprove the facts of the issue. What will evidence collected at a scene do for the investigation -

* May prove that a crime has been committed.
* Establish any key elements of a crime.
* Link a suspect with a scene or a victim.
* Establish the identity of a victim or suspect.
* Corroborate verbal witness testimony.
* Exonerate the innocent.

The evidence that is located and recovered at a scene will give the detectives responsible for the investigation leads to work with in the case.

Types of Evidence

o Impressions include fingerprints, tool marks, footwear, fabric impressions, tire

marks and bite marks.
o Forensic Biology includes blood, semen, body fluids, hair, nail scrapings, blood stain ptterns,
o Trace Evidence includes gun shot residues, arson accelerant, paint, glass and fibers.
o Firearms - includes weapons, gun powder patterns, casings, projectiles, fragments,

pellets, wadding and cartridges.

Personnel Duties and Responsibilities

There are certain personnel duties and responsibilities which are necessary in almost any major crime investigation operation. Those enumerated herein concentrate on the ones which are typically crucial to ensure that such efforts are conducted in an organized and methodical fashion. It is important to note it may not be feasible to have one person assigned to each duty. It is relatively common for one person to accomplish two or more duties.

For all positions, interest and attitude of personnel are paramount concerns. Training and experience will only be used to best potential when team members possess a positive attitude. This human side of evidence response teams is significant due to the long hours and attention to detail often required of personnel.

The major assignments, as well as corresponding general duties and responsibilities, are set forth as follows:

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

Team Leader

1. Assume control - ensure safety of personnel and security at scene. Ensure personnel use appropriate protective equipment and follow standard recommendations to protect them from any health hazard which might be presented by blood or any other human body fluid.
2. Conduct initial walk-through for purposes of making a preliminary survey, evaluating potential evidence, and preparing a narrative description.
3. Determine search patterns, and make appropriate assignments for team members.
4. Designate command post location and ensure exchange of information between search and investigative personnel.
5. Coordinate with other law enforcement agencies and make sure a cooperative spirit is maintained.
6. Ensure that sufficient supplies and equipment are available for personnel.
7. Control access to the scene and designate an individual to log everyone into the scene.
8. Continuously reevaluate efficiency of search during entire course of operation.
9. Release the scene after a final survey and inventory of the evidence has been done.

Photographer and Photographic Log Recorder

1. Photograph entire area before it is entered.
2. Photograph victims, crowd, and vehicles.
3. Photograph entire scene with overall, medium and close-up coverage, using measurement scale when appropriate.
4. Photograph major evidence items before they are moved; coordinate this effort with Sketch Preparer, Evidence Recorder, and Evidence Recovery Personnel.
5. Photograph all latent fingerprints and other impression evidence before lifting and casting are accomplished.
6. Prepare photographic log and photographic sketch.

Sketch Preparer

· Diagram immediate area of scene and orient diagram with sketch.
· Set forth major items of evidence on sketch.
· Designate and label areas to be searched and advise team leader and all other search members of nomenclature for designated areas.
· Obtain appropriate assistance for taking measurements and double check measurements.
· Ensure necessary administrative information, such as scale disclaimer (not drawn to scale), is recorded on sketch.

Evidence Recorder / Custodian

o Have significant evidence photographed before collection.
o Describe evidence and its location on appropriate bag or envelope.
o Sign and date evidence container/maintain chain of custody.
o Appropriately collect and package evidence to maximize evidence integrity.
o Maintain evidence log.

o Use appropriate protective equipment (gloves) and methods when dealing with potentially infective evidence (blood).
o Documents in question

Processing the Crime Scene

In an Organized approach to Crime Scene Investigations there are three (3) basic and simple stages in properly processing the crime scene. Those stages consist of –

· Scene Recognition,
· Scene Documentation and
· Evidence Collection.

An organized approach is a sequence of established and excepted duties and protocols.

An organized approach assures:

oo A thorough and legal search is conducted.
oo Expeditious processing without compromise.
oo Proper scene documentation.
oo Proper methods and techniques for evidence recovery.
oo Proper use and knowledge of resources and equipment.
oo All pertinent evidence recovery.
oo Proper handling and packaging of evidence.
oo Proper distribution points for evidence analysis.
oo Proper safety precautions are followed.