Police chiefs are convinced the £140,000 paid to informants in the past three years provided ‘excellent value for money’.

Suffolk Constabulary paid an average annual sum of almost £46,000 to covert human intelligence sources – commonly known as police informants.

The force would not disclose how many people had been paid for information – or the highest amount given to an individual – but they said strict procedures were in place to ensure the intelligence gathering practice was carried out ethically.

Confidential informants, including offenders and other sources of information with knowledge of criminal activity, are paid as a means of gathering evidence otherwise unobtainable through traditional tactics.

Figures obtained under the Freedom of Information Act showed police paid out £45,666.78 in 2016/17, £48,894.32 in 2015/16 and £43,358.98 in 2014/15.

The force said revealing the number of payments, and highest amount paid to an individual, could have an impact on retention, recruitment, operational vulnerability and identification.

Controls on using informants include the Regulation of Investigatory Powers Act, which permits recruitment if necessary to national security, or preventing or detecting crime and disorder.

A police spokesman said the use of covert human intelligence sources was an important element of the policing model, enabling the gathering of intelligence otherwise be unavailable.

“Such intelligence makes a very positive contribution in our fight against crime and disorder, and allows us to target criminals of every kind,” they added.

“There are strict procedures in place, underpinned by regular inspections, to ensure we operate in an ethical manner and make the best possible use of resources.

“The amount we spend on obtaining intelligence in this way represents, in the police view, excellent value for money.”

Police and Crime Commissioner (PCC) Tim Passmore said the total represented a very small proportion of the budget, adding: “Paying informants is a legitimate component of policing for gathering intelligence in order to solve and prevent crime.

“Clearly, as PCC I must ensure the chief constable spends public money sensibly, which I monitor regularly, and I am satisfied this is a justifiable use of the policing budget.”