DNA analysis today
DNA analysis has been used in criminal prosecution for many years. DNA profiles can be generated in one of two ways:
- from a DNA sample taken from a person, for example by means of a buccal swab;
- from a DNA sample taken from traces found at a crime scene, such as hair, skin cells, blood, semen or saliva.
DNA profiling is only permitted for solving crimes or identifying deceased or missing persons and must be ordered by a public prosecutor or court.
Types of matches
DNA profiles are stored and processed in the national CODIS database (Combined DNA Index System). The database is used to compare DNA profiles generated from people or trace samples (i.e. blood, fingerprint, etc.). It can turn up the following types of matches:
- trace-person match:
A DNA profile generated from a trace sample found at a crime scene matches the DNA profile of a person already registered in the database. The police may then interview the person in order to determine the reason for their presence at the crime scene.
- trace-trace match:
The DNA profile from a trace sample matches one that is already in the database, i.e. it comes from the same person, but that person has not yet been identified. This type of match allows law enforcement services to link two crime scenes to the same person.
The CODIS database
The standards and framework conditions for the CODIS database are laid down in law. Only fedpol’s DNA Coordination Unit, which operates the database, and the DNA laboratories have access to the profiles.
Particular importance is attached to protecting the rights of individuals. Only information from the non-coding parts of the DNA (forensic DNA profile) is used to assess the standardised DNA profile of a person. Furthermore, the database containing the DNA profile data is physically and administratively separate from the database containing the person and case data. The data is only linked if there is a match.
Last modification 11.05.2023