PSNI shelled out £2m in last five years for tip-offs from network of informants
Police have paid out almost £2m for information and tip-offs about criminal activity in the last five years, the Belfast Telegraph can reveal.
Around £800 a day is being spent running the PSNI's network of touts and informers.
In the last year alone the bill was almost £300,000.
It is among the highest payouts of any police force in the UK, and is believed to be second only to the Metropolitan Police.
The disclosure will reopen the debate on the use of informants, which has long been a controversial issue in Northern Ireland.
Police insist it is a price worth paying, leading to information that helps solve serious crime.
But others have voiced concerns over accountability and whether money should be paid to people who themselves are often involved in crime.
SDLP Policing Board member Dolores Kelly said she understood why some would be uncomfortable. "Most people will consider it anathema that people are being paid to give information which others might more freely disclose," she said.
"But these are very dangerous circles that these people potentially move in. The management of informants by police is of a very high standard.
"Nobody will be comfortable with having to pay this money. However, the oversight arrangements are such that we have confidence in the system."
The PSNI's expenditure on informers, known formally as Covert Human Intelligence Sources (CHIS), was disclosed after a Freedom of Information request.
In the 12 months to March 31 this year, the bill was £297,158 - some £814 a day. The costs have fallen when compared to previous years.
During 2013/14 a total of £466,332 was spent running informers, while last year the expenditure came to £375,730. In the five years since April 2011, the total bill was £1,995,392.
It is thought not to include intelligence relating to national security and dissident terrorism, which would come largely under the remit - and budget - of MI5. The PSNI refuses to discuss its use of informers, including how many it uses, where they are located or if any have criminal convictions. PSNI Assistant Chief Constable Will Kerr defended the expenditure.
"Intelligence plays a key role in the PSNI's ability to provide an effective policing service," he told the Belfast Telegraph.
"The information provided is processed professionally and is used to assist officers to combat threats posed by drugs, burglaries, child abuse and a range of other issues which cause communities concern. Without intelligence we could not function effectively as a police service in our obligation to keep people safe.
"All our activities in relation to the handling and management of intelligence are subject to extensive scrutiny and full accountability to the office of the Surveillance Commissioner."
The use of informants in Northern Ireland remains highly controversial. In 2007 a report by then-Police Ombudsman Nuala O'Loan concluded that RUC officers protected loyalist informers from probes into more than a dozen murders.
These included the killings of Raymond McCord jnr and Catholic taxi driver Sharon McKenna, who was gunned down in 1993. Mrs Kelly said spending on informants was carefully scrutinised by the Policing Board.
"We routinely ask questions and meet with the Chief Constable and the senior team around such matters," she added. "We will probably never know the amount of serious crime prevented or solved by the giving of this information."
DUP Policing Board member Jonathan Craig added: "It is a necessary evil. Unfortunately some people will only respond to a financial incentive.
"But that incentive saves lives and convicts criminals who are trying to damage the fabric of our society."
In its response, the PSNI defended its decision not to disclose more information.
"The Police Service is charged with enforcing the law, preventing and detecting crime and protecting the communities we serve," it said.
"The security of the country is of paramount importance and the Police Service will not divulge whether information is or is not held if to do so would place the safety of an individual at risk or undermine national security and compromise law enforcement. Whilst there is a public interest in the transparency of policing operations and providing assurance that the Police Service is appropriately and effectively engaging with the threat posed by terrorists/criminals, there's strong public interest in safeguarding both national security and the integrity of police investigations and operations."
The use of informants is monitored by the Regulation of Investigatory Powers Act 2000.
The protocol includes recording all handling of an informant, using only trained staff, and ensuring there is supervision of officers involved.
An informant may, in an authorised operation, infiltrate a criminal conspiracy or be a party to the committing of criminal offences, within the limits recognised by case law and with the approval of the authorising officer. Acting beyond these limits could lead to prosecution - the need to protect the source cannot alter this.