Criminal Investigation Week 1

Lecture: We will discuss some of the specialists involved in the forensics field. 

1.      Crime scene investigator.  These people respond to a crime scene and locate, collect, package, and transport evidence to storage for future analysis.

2.      Latent Print Examiner.  This specialty requires additional training and involves comparing latent prints found at a crime scene with inked prints of a suspect to confirm or deny a match.  Since the invention of automated fingerprint systems, this person also codes and enters crime scene latents into AFIS.

3.      Firearms examiner.  This specialty also requires additional training.  The examiner looks at firing pin imprints, shell casings, and bullets, for distinctive marks left by the gun that fired them.  Both evidence left at a crime scene and a suspect firearm are needed for comparison. 

4.      Tool mark examiner.  Similar to a firearms examiner, this expert compares tool marks left at a crime scene (e.g. pry marks on a door frame) with a tool (like a pry bar) that could have made the marks.

5.      Document examiner.  This is a wide field involving fraudulent checks and other documents, verifying signatures, determining if authentic documents have been altered, and if a particular copy machine made a questioned document.

6.      Trace evidence examiner.  Oftentimes a scientist, this person uses the comparison microscope and spectrometer to compare hair, fibers, glass, soil, paint, and other compounds to determine their type and origin (Adapted from “Blood Spatter, FSB03.”)

We will also go through your evidence bag and explain the use of those tools, which include gloves, face masks, latent fingerprint tools, and plaster cast materials. 

To finish out the class session we will go over the steps in a crime scene investigation: arriving, officer safety, check for injured and call for medical help, secure scene and identify immediate witnesses, broadcast suspect information, search for evidence, photograph scene and evidence, measure for sketch, and collect evidence and interview witnesses. 

          Back to Criminal Investigation


       Christopher Bruno