A former Metropolitan Police officer began a sexual relationship with a woman while he was investigating her, an investigation has found.
John McCarthy, who was a detective constable at the time, began sleeping with the woman in 2017 while investigating her for harassment, a probe by the Independent Office for Police Conduct (IOPC) found.
During their relationship Mr McCarthy also sent the woman sexual text messages, it found.
The harassment case against her was subsequently discontinued.
Mr McCarthy also borrowed £3,580 from the woman in a series of payments between June and September 2017, the IOPC found.
The IOPC said it had found evidence that Mr McCarthy never intended to pay the woman back.
The then-DC did not declare his relationship with the woman, nor the money he had received from her, it said.
However, an investigation into Mr McCarthy was launched in January 2018 following a referral from the Met Police.
In March 2020 the investigation found that there was a case for gross misconduct against the officer.
Mr McCarthy then resigned from the force on September 5 this year.
In a statement, IOPC regional director Sal Naseem said: “It is clear John McCarthy took predatory steps for his own sexual gratification and personal gain.”
Mr Naseem added that Mr McCarthy’s behaviour has had a “corrosive” effect on the public’s trust in the police.
“His behaviour has had a serious and devastating impact on his victim, and a corrosive, lasting impact on the public’s confidence in individual officers and the police service in general,” he said.
A police disciplinary panel ruled that Mr McCarthy would have been dismissed without notice for gross misconduct had he not already resigned.
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