Latent Print Comparison
Latent Print Comparison Section
FrictionRidge@washoecounty.gov
Anastacia Melendy, Supervising Criminalist
Main Phone: (775) 328-3380
amelendy@washoecounty.gov
The Forensic Science Division conducts the following with regard to latent fingerprint identification:
- Evaluate and compare all of your latent lift cards and reference prints.
- Search your latent prints in WIN/ABIS.
- Supply expert testimony in any court proceedings as required.
The Latent Print Comparison section examines all latent impression evidence submitted by agencies for the purpose of source identification.
The Latent Print Comparison section utilizes the ACE-V methodology during their examination of latent impression evidence.
ACE-V is a discipline standard methodology that stands for Analysis, Comparison, Evaluation, and Verification.
Analysis is the assessment of a friction ridge impression to determine suitability for comparison.
Comparison is the direct or side-by-side observation of friction ridge details to determine whether the detail in two impressions is in agreement based upon similarity, sequence, and spatial relationship.
Evaluation is the formation of a conclusion based upon analysis and comparison of friction ridge impressions. Conclusions that can be reached are: Identification, Exclusion, or Inconclusive.
Verification is the independent examination of an initial conclusion by another qualified examiner as a quality control measure.
Western Identification Network / Automated Biometrics Identification System – WIN/ABIS
WIN/ABIS is a multi-state network that has the ability to search criminal and non-criminal fingerprint records. Fingerprints collected from crime scenes, or collected from items submitted to the laboratory for analysis, are entered into the WIN/ABIS network and searched against over 29 million fingerprint records. Additionally, WIN/ABIS interfaces with local agencies in California and the national FBI databases. Suitability for fingerprint database search/entry is determined by qualified personnel in the Forensic Science Division’s Latent Print Comparison Section. Fingerprint searches that fail to yield an identification can be registered to search against future arrestee and non-criminal records. Please note that not all submitted latent prints will have sufficient quality for database entry and/or registration. The database searched, the results of the search, and/or fingerprint registration will be stated in an official report.
The WIN/ABIS system does far more than identify the individual you have in custody; it will also search the individual latent print that you develop from a crime scene. If you submit latent lift cards to this lab for evaluation and computer search, you can be assured that regardless of the type of crime, we will search any prints that are of value against the computer database. Palm prints can also be searched. The computer search is predicated upon a core/axis placement and minutia alignment, which must be determined by the latent examiner. The high tip area of the fingers, extreme side portions of the fingers, and second/third joints cannot be searched on the computer; however, they can be manually compared to major prints submitted by the requesting agency.
The majority of latent prints developed at crime scenes that are submitted for comparison can be searched on the computer. If the search is positive and identification is effected, you will be notified and a report will follow. If no identification is effected, then the latent print will be registered in the "unsolved latent database" file. By registering a print, the print will be searched against future arrestees within the WIN network. The latent print will remain in the computer until it is identified or the statute of limitations has expired.
If there is a suspect in the case, submit a ten-print card along with your request. If a ten-print card cannot be obtained by the user agency the Latent Print Examiner will contact the state repository. In order for the Latent Print Examiner to receive a ten print card from the state repository, all the suspect's demographic information including their SID and FBI reference number if applicable is required on the Examination Request Form.
