Outside of the security and intelligence agencies such as GCHQ, around 600 public authorities hold the power to request communications data. In his 2015 report, the Independent Reviewer of Terrorism Legislation, David Anderson QC, distinguished between “major” law enforcement agencies, including police forces – who make the great majority of requests for communications data – and “minor users” of data including other national public authorities such as Ofcom and the Gambling Commission, as well as the 430 local authorities. 
A further distinction can be made between the small number of bodies which have the power to intercept communications, under RIPA Part 1 Chapter 1, and those that do not. The law enforcement bodies with this power are the National Crime Agency, the Metropolitan Police Service, the Police Service of Northern Ireland, Police Scotland, and Her Majesty’s Revenue and Customs. According to the 2015 IOCC report, 2,795 interception warrants requested by these bodies were approved in 2014; 68% concerned serious crime and 31% were related to national security. 
 David Anderson Q.C., ‘A question of trust’, Report of the Investigatory Powers Review, July 2015, p.166
 Rt. Hon. Sir Antony May, ‘Report of the Interception of Communications Commissioner’, March 2015, pp.26-28.