Crime Scene Investigators

There are eleven Crime Scene Investigators and two Crime Scene Supervisors assigned to the Crime Lab. Investigators are responsible for investigating crimes such as homicides, suicides, dead bodies, robberies, rapes, drive-by shootings, assaults, burglaries, auto thefts, and any other crime where a specialized skill is needed. Other responsibilities may include attending autopsies. Special equipment and techniques are used by the Crime Scene Investigators.

After the investigators complete their investigation at the scene, they return to the laboratory to process any evidence they have collected and type reports. Every hour on the scene generates an hour of paperwork in the lab.

The Crime Scene Investigators document the scene by first photographing, (general to specific, outside to in). Then they diagram and measure the scene and evidence. Next, they collect any and all evidence pertaining to the case. The investigators may spend a short time or several days to completely document and process the scene. The Crime Scene Investigators investigate between 1,800 to 2,100 cases a year.

Latent Print Section

Fingerprints are a chance impression of the ridges found on the hands that can be transferred to a surface. A latent print is 99% water and 1% amino acids and other compounds. Fingerprints can be found on non-porous surfaces such as glass and on porous surfaces such as wood. These impressions usually need some type of enhancement to be visible. There are numerous chemical means to develop fingerprints. Just because a person touches a surface does not mean he/she will leave their fingerprint behind. There are several reasons for this. First, the finger may not have enough transfer medium (perspiration, oil, ink, etc.) to leave an outline of the ridges on a surface. Secondly, the receiving surface may not be conducive to receive a print (a smooth, clean window versus a dirty, rusty wrench). And lastly, the environment will affect a latent print. Fingerprints are very fragile so wind, rain and heat can destroy them easily and quickly.

The Crime Lab has three Latent Print Examiners. Their responsibilities include processing evidence for latent prints as well as the examination of latent prints to determine their suitability for comparison. They compare latent prints to the known prints of named individuals on a case. They enter unidentified latent prints into the Automated Fingerprint Identification System (AFIS) and/or Next Generation Identification (NGI). Approximately 4,000 latent prints per year are handled by the Latent Print Section.

Digital Evidence Technicians

The WPD Crime Lab has two Digital Evidence Technicians. They are responsible for collecting and disseminating digital evidence. Work performed is a specialized support function that is unique to law enforcement that requires both technical field and laboratory work. Work may be diagnostic in nature involving the use of specialized hardware and software. This work follows industry standard and best practices, and use of independent judgment while solving technical problems.