The following properties of friction ridge characteristics are used in identification process:

• uniqueness (unique arrangement for each individual),
• immutability (arrangement of features remains unchanged during lifetime),
• irremovability.
• Fundamental tasks of Fingerprint Identification Unit include determination of the following:
• person, who left fingerprints at a scene of crime
• person, who left lip print at a scene of crime
• person who left ear print at a scene of crime
• how a glove impression was left.

Lip print and earprint examinations are performed solely in CFLP Fingerprint Department.

In order to confirm their competence, experts of this Unit regularly participate in proficiency testing in the area of fingerprint identification, organized by external institutions.

Fingerprint identification experts supervise the recruitment process for candidates for experts. They are also responsible for scientific level of expert activities performed in nationwide police forensic laboratories. To facilitate the whole process, guidelines for conduct of testing in fingerprint identification were developed, consultations are provided, in addition to trainings and in-house apprenticeship for candidates on the way to a final exam.

Every year, proficiency testing is performed for regional police fingerprint units according to the “Conduct of proficiency testing through interlaboratory comparisons in the area of fingerprint identification” procedure. This is done with a view for ensuring high level of forensic casework. Fingerprint identification experts take part in interlaboratory cooperation programmes, organised within ENFSI (European Network of Forensic Science Institutes) Fingerprint Working Group.