Automated Fingerprint Identification System (AFIS)

August 30, 2020

When friction ridge impression evidence is collected from a crime scene, investigators do not know who it belongs to, and may not have any suspects in the case. In these instances, the recovered impressions can be submitted to the DPS Crime Laboratory AFIS Section for analysis in order to help determine who committed the crime in question.

The Automated Fingerprint Identification System is a critical tool utilized by the Department to assist investigators by creating leads in cases. AFIS has the ability to classify, match, and store fingerprints and palm prints and contains prints from both criminal and applicant records.

Friction ridge evidence analysis in the AFIS section consists of many essential steps that result in the final information provided to investigators. The first step in the process is an analysis of the evidence to determine if the prints on it have sufficient clarity and meet the criteria for an AFIS search. Next, the forensic scientist will capture an image of the evidence and import it into AFIS, and then mark all the visible ridge characteristics within the print as well as other features such as the core and axes of the print. After the search is submitted, AFIS uses complex algorithms that enable the system to find the closest matching known prints among the millions that the database contains. Once the candidate list is received, the scientist visually compares the unknown impression to the known prints that AFIS has presented to determine if one of the candidates is a match. If no candidate is determined to be the source of the unknown print then it is registered in the Unsolved Latent Database where it is continuously searched against incoming arrest or applicant prints.

The forensic scientist's primary AFIS search is of the State of Texas' database. Then, depending on the offense in the case, the unknown prints may also be searched in the Federal Bureau of Investigation database (NGI, formerly IAFIS), the Department of Homeland Security database (IDENT), and the Department of Defense database (ABIS), and potentially stored in their respective unsolved databases for future searches against incoming prints. 

Once all suitable unknown prints in a case have been searched, a report is prepared which outlines the results of the examination.

In addition to working cases submitted directly to them, the AFIS Section also works closely with the DPS Crime Laboratory's Friction Ridge Sections located throughout the state, performing AFIS searches for them when their comparisons of unknown prints to suspect prints have not yielded identifications.

Though the AFIS section performs casework as its primary duty, it is also responsible for the training of AFIS operators from local agencies all over the state of Texas in the execution of AFIS searches on the State of Texas AFIS as well as the FBI's Universal Latent Workstation (ULW) software.