A SCOTS policeman did not die accidentally during a drug-fuelled sadomasochistic sex session, jurors at the officer’s murder trial have been told.

Crystal meth addict Stefano Brizzi, 50, allegedly murdered and then chopped up Metropolitican Police officer Gordon Semple, who was originally from Inverness, after they met through a gay dating app in April this year.

The Italian social worker claimed Constable Semple, 59, died after a leash around his neck momentarily slipped during a sex game, the Old Bailey in London heard.

However, pathologist Dr Benjamin Swift, who carried out the post-mortem examination on his body, told the jury pressure would have had to be applied for minutes not seconds as claimed by Mr Brizzi.

In his defence statement, Mr Brizzi claimed the officer had visited his south London flat and they took crystal meth and poppers, watched porn and had sex He claimed Mr Semple wanted to be restrained, so Mr Brizzi put a hood over his head and tied a leash around his neck to pull on while sitting on Mr Semple’s face.

He said they were interrupted by someone knocking on the front door, but Mr Semple indicated he wanted him to go away.

Crispin Aylett, QC, prosecuting, said: “A third party knocked on the door. The defence statement suggests Mr Semple was still alive, conscious and able to motion with a finger to turn the third party away.

“It was during this time that the deceased asked the defendant to tighten the collar as much as possible. Whilst tightening the leash, it apparently slipped.”

Mr Brizzi claimed he heard a snap, and realised Mr Semple was unconscious and had no pulse, it was said.

He said he panicked and became paranoid after searching Mr Semple’s clothes and discovering he was an officer, so took more drugs and started to get rid of the body.

Dr Swift said the pressure on the neck would have needed to be applied for longer to have killed him. Less than 20 seconds, “potentially” less than 10 seconds, could result in unconsciousness, he told the jurors.

He added: “However, release of the pressure on reaching unconsciousness will result in the individual awakening rapidly.

“To result in death, the force needs to be maintained beyond the point of unconsciousness – potentially minutes – to result in oxygen starvation of the brain.

“It’s possible the deceased might have suffered fits during this time as a result of a lack of oxygen to the brain.”

He said the cause of death was “unascertained” because of the extensive dismemberment.

Dr Swift said body parts were delivered to him in plastic boxes to examine, but the brain has never been recovered.

Forensic scientist Cathryn King confirmed there was a one-in-a-billion match of Mr Semple’s DNA to the pool of fat and grease in the oven.

Mr Brizzi denies murder but admits obstructing the coroner.

The trial continues.