Matthias Monroy

For two years now, the largest European police database has had a technique for cross-checking dactyloscopic data. The proportion of false hits is said to be in the per mille range. A comparable German system contains data records on 5.3 million persons.

In 2013, the EU Commission completed years of work on upgrading the Schengen Information System to the second generation (SIS II). Since then, it has also been possible to store fingerprints in Europe’s largest police database. The European Agency for the Operational Management of Large-Scale IT Systems (eu-LISA), which is organisationally responsible for SIS II, has set up an „Automatic Fingerprint Identification System“ (AFIS) for this purpose. Its use is regulated in the latest version of the SIS II Regulation.

However, it has only been possible to search this biometric data since 2018. In this way, an unknown person who gives no or false personal details in a police check can be identified with their dactyloscopic data. This requires that the person concerned has previously been put on the wanted list in the Schengen Information System.The system can be used for arrest, clandestine observation, deportation, prevention of re-entry or as a missing person.

Responsibility of the BKA

After a transitional period of two years, the use of the AFIS in the SIS II will be obligatory for all Schengen member states as of 28 December 2020. From now on, every new fingerprint stored in the database is to be compared with the existing data. The responsible SIS contact points (the so-called SIRENE network) must have created the technical prerequisites for this. In Germany, this responsibility lies with the Federal Criminal Police Office (BKA), which was one of the first participants in the system.

As of today, almost 300,000 fingerprints are stored in SIS AFIS. This was announced by the German Federal Ministry of the Interior in its answer to a parlamentarian question. Compared to 2018, this is roughly a doubling.

The number of persons identified via such a query also initially increased significantly after the system was set up. In 2019, German police authorities obtained a total of 9,041 hits in the EU police database via fingerprint matching, (2018: 2,395). The number has dropped to 5,618 hits for 2020. The ministry does not give any reasons for this, but perhaps the decline is due to the sharp reduction in border crossings in the wake of the Corona pandemic.

In future, unknowns will also be stored

The dactyloscopic data are processed in the SIS II in so-called „fingerprint sheets“. Their storage is done in the proprietary format of the respective manufacturer, the exchange is then done via a NIST standard. According to the answer now available, false hits are in the per mille range. According to this, three German hits were detected as „false positives“ in 2020. These were subsequently reported to eu-LISA.

The manufacturer of SIS AFIS is the French company IDEMIA. The company is the European market leader in the field of biometric systems and is also installing the new common „Biometric Matching Service“ on behalf of the EU Commission. The application costs 300 million Euros and will process fingerprints and facial images that will be merged by the EU Commission into a „Common Identity Repository“. It will contain biometric data from six EU databases.

So far, fingerprints and facial images can only be stored as an annex to existing personal data in the SIS II. In future, it will also be possible to store an „unknown wanted person“. Then law enforcement authorities will be able to enter crime scene evidence into the SIS II. This is already technically possible in the central system, now the member states must implement the system nationally.

BKA makes suggestions for improvement

At a later stage, the exchange of follow-up information is also to be improved. This is the procedure after a hit in the AFIS, in which the „possessing“ member state releases the corresponding data upon request. The BKA had already made corresponding technical proposals for this, including the use of uniform data formats and processes.

In addition to the SIS AFIS, the German police also use a purely national fingerprint system. It contains currently 5.3 million personal data, including 2.1 million with palm prints. Such national AFIS systems can also be searched Europe-wide via the Prüm Decision.

In contrast to SIS II, it is already possible to store unknown persons in the German AFIS. According to the Federal Ministry of the Interior, there are currently about 458,000 unsolved crime scene traces stored in the file. This data could be transferred to the SIS II at the click of a mouse, after the corresponding prerequisites have been created there.

Image: European Parliament.