A police sergeant was never questioned after fellow officers spotted him in a sex tape filmed in the home of a paedophile, former detectives have claimed.

Whistleblowing ex-officers from the South London Child Abuse Investigation Team (CAIT) said a horde of illicit videos were discovered during a raid, showing a string of men having sex with the paedophile’s wife.

“It was quite apparent from the footage that they weren’t aware of what was going on,” said former detective Tom Coling, the lead officer in the case.

Among the men secretly filmed was a Met Police officer.

“He was in full uniform and had his radio going, which indicated that he was on duty at the time,” said Tom.

“I was pulled in to see if I recognised him,” confirmed Jan Pyle, another former detective in the unit.

The Met has not denied the pair’s account.

Both officers left the force in 2014.

Tom said he was bullied out after raising concerns over police misconduct.

Jan said she resigned, feeling overworked and disillusioned.

Both are speaking out in a series of reports by the News Shopper.

After the raid, they said, the paedophile was charged with child sex offences and his wife with voyeurism offences over the videos.

The officer in the video, identified by his shoulder number, had since risen to a more senior rank, then been sacked over unrelated sexual misconduct.

“I was given a direction to write to the officer once we had identified who he was,” said Tom.

But when he failed to respond, Tom said nothing else was done.

“No one spoke to him, to say ‘We know you were at the scene where vulnerable children were being raped’,” said Tom.

“No questions were ever asked. That just seems very, very wrong.”

Jan said the charges against the man's wife were then dropped.  

Tom said he believed the dropping of the charges was at least in part due to the embarrassment that would be caused if the officer’s visit to house came out in court.

“I didn’t think it was the right decision,” he said.

The story remained untold until today.

The Met Police did not comment, other than to say it expects “the highest level of professional conduct” and ensures misconduct is “thoroughly investigated… with the appropriate sanction applied as a result.”

“We also seek to learn from each case to protect against the incident occurring again,” it said, adding that on July 17, it launched a “New Met for London” plan, whereby officers committing misconduct would be “dealt with swiftly and robustly”.