{{no footnotes, date=April 2019
The National Identification Service (NIS; also called SO4 from its
Specialist Operations
The Specialist Operations directorate is a unit of the Metropolitan Police in London, England. It is responsible for providing specialist policing capabilities, including national security and counter-terrorism operations. As of May 2025, the Spe ...
designation) is a department of the
London
London is the Capital city, capital and List of urban areas in the United Kingdom, largest city of both England and the United Kingdom, with a population of in . London metropolitan area, Its wider metropolitan area is the largest in Wester ...
Metropolitan Police which provides a range of support services on behalf of the Metropolitan Police and other police forces.
All SO4's services are connected with
criminal record
A criminal record (not to be confused with a police record or arrest record) is a record of a person's criminal Conviction, convictions history. The information included in a criminal record, and the existence of a criminal record, varies betwe ...
s and include a remit to act as the National Identification Service (NIS). The Metropolitan Police has had a national role in keeping criminal records since the 18th century but it was not until 1913 that the Criminal Record Office was established at New Scotland Yard. The NIS had sole responsibility for maintaining the national database of criminal records until 1995 but, since then, each police force in
England
England is a Countries of the United Kingdom, country that is part of the United Kingdom. It is located on the island of Great Britain, of which it covers about 62%, and List of islands of England, more than 100 smaller adjacent islands. It ...
and
Wales
Wales ( ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by the Irish Sea to the north and west, England to the England–Wales border, east, the Bristol Channel to the south, and the Celtic ...
has been responsible for updating its own records on the
Police National Computer
The Police National Computer (PNC) is a database used by law enforcement organisations across the United Kingdom and other non-law enforcement agencies. Originally developed in the early 1970s, PNC1 went 'live' in 1974, providing UK police for ...
. The NIS continues to provide a number of centralised maintenance and disclosure services for police forces.
SO4 also conducts background checks on London residents or former residents who have applied to the
Criminal Records Bureau
In ordinary language, a crime is an unlawful act punishable by a state or other authority. The term ''crime'' does not, in modern criminal law, have any simple and universally accepted definition,Farmer, Lindsay: "Crime, definitions of", in Cane ...
for an enhanced disclosure, deals with subject access requests under the Data Protection Act and publishes the '' Police Gazette'' on behalf of the UK Police Forces.