Phoenix Police Department Laboratory Service Bureau

Vision Statement
“The mission of the Laboratory Services Bureau is to make Phoenix the safest major city by providing excellence in forensic science analysis."

The Phoenix Police Department Laboratory Services Bureau is a nationally accredited forensic laboratory that provides technical assistance and training, evaluates and analyzes evidence, interprets results and provides expert testimony related to the full spectrum of physical evidence recovered from crime scenes. Some of the scientific procedures utilized by the laboratory have the potential for linking a suspect to a crime, victim, or a scene.

The Phoenix Police Department Laboratory Services Bureau consists of over 100 professional staff and is comprised of eight specialized sections which include Evidence Processing, Latent Prints, Crime Scene Response, Forensic Biology, Controlled Substances, Questioned Documents & Trace, Toxicology, and Firearms.

Laboratory management recognizes that the Laboratory is one element of a multifaceted "criminal justice system” and that scientific results generated by the Laboratory may be used by any element of that system. The goal of the Phoenix Police Crime Laboratory is to generate accurate, impartial, and timely scientific examinations and opinions for the criminal justice system in the interest of enhancing public safety.

Comparative Analysis
The Comparative Analysis Section analyzes and compares physical evidence, normally microscopic in size, which has been transferred from one item or person to another. This evidence often consists of hairs, fibers, paint chips, glass fragments, and similar items. Other examinations routinely performed in the section include shoeprint and tiretrack comparisons, duct tape comparisons, explosive analysis, headlamp examinations, and gunshot residue kit analysis.

Crime Scene Response
The Crime Scene Response Section is staffed 24 hours a day, 7 days a week by Evidence Technicians. They are in mobile units that respond to crime scenes citywide. These scenes range from property crimes to homicide and death investigations. Annually, there are over 10,000 requests for their services each year.

The primary responsibilities of the Crime Scene Response Section is to respond and photographically record crime scenes, as well as to identify, collect and preserve physical evidence that may also be present at the scene. Evidence Technicians are also required to testify in court at all levels of the judicial system.

Firearms
The Firearms Section performs examinations of firearms, ammunition, and related evidence. Examinations include comparisons of fired bullets and cartridge casings to suspect weapons, function testing firearms, bullet and casing examinations to "predict" weapons used, muzzle to target distance determinations, trajectory analysis, serial number restoration, and gunshot residue analysis.

Firearm Examiners also offer expert advice on weapons and ammunition and use a national computer database to potentially link weapons to crime scenes. Knowledge of and experience with firearms are assets to potential candidates who meet the criteria for "Criminalist."

Latent Print Processing

The Latent Print Processing Section is comprised of Evidence Technicians and Latent Print Examiners. Personnel perform examinations on physical evidence submitted from crimes scenes and recover latent prints from glass, plastic, paper, metals, and various other surfaces. Members perform chemical and physical analyses to develop and identify friction ridge detail using powders, chemicals, alternate light sources, and photographic techniques. In addition, Latent Print Examiners evaluate latent prints submitted by field officers, crime scene, and evidence technicians. Examiners work extensively on the entry and verification of images in the Arizona automated fingerprint system. Examiners and technicians also testify in court regarding their techniques and findings.

Latent Print Comparison

The Latent Print Comparative Section performs all work related to the comparison of latent prints recovered from evidence submitted to the Laboratory Services Bureau. Latent prints are impressions left by the ridged skin on the fingers, palms, toes and soles of the feet of people. Latent print examiners (LPE) analyze and compare latent prints to the known inked prints of individuals to establish identifications or exclusions. The Phoenix Police Department is linked to the Arizona Automated Fingerprint Identification System (AZAFIS). The Arizona Automated Fingerprint Identification System is a computer-based tool that allows the Latent Print Examiner to search an unknown latent fingerprint against the approximately 6.5 million individual fingerprints in the database. The AZAFIS will produce a list of candidates of possible matches. The AZAFIS does not make the identification. It is the skilled eye of the Latent Print Examiner that will determine if a match has been found to the unknown latent print. Plans are now being made to link the AZAFIS to the FBI Integrated Automated Fingerprint Identification System (IAFIS). This will allow access to a national database of known fingerprints. A Newly developed computer-base Automated Palm Print Identification System is also planned for future implementation. When asked to do so the Latent Print Examiner will also provide expert witness testimony in court regarding all facets of latent print identification. The Latent Print Comparative Section is staffed by Latent Print Examiners that have been tested and achieved certification by the International Association for Identification (IAI). A professional certification currently held by less than 1000 latent print examiners in the world.

Toxicology
The toxicology section has four main responsibilities: 1. Blood alcohol determinations. 2. Supporting the breath testing program. This includes maintaining the instruments, providing training on the proper use of breath testing instruments, and assisting in the training of new personnel at the City Prosecutors Office. 3. Testing for toxic vapors. These can be found in common household items such as paint, glue, and correction fluid. 4. Identifying drugs, poisons, and other substances in bodily fluids.

Due to the volume of DUI cases in Phoenix and the tenacity in which they are litigated, members of the toxicology section may be required to testify often. Providing training and expert testimony result in an increased interaction with those outside the laboratory. Therefore, good communication skills are essential.

Contacting the Lab
Contact us at 602.262.6197.

For information about working in the laboratory read our recruitment guide Click Here.