A 65-year-old man has been cleared of murdering a retired Fettes College teacher but has been convicted of perverting the course of justice for dumping the body and lying to the police.

Paul Black had been accused of killing Peter Coshan, 75, on either August 11 or 12 2022 as part of a catfishing plot with his flatmate, Paul McNaughton, to steal tens of thousands of pounds.

The former biology teacher was murdered in Black’s flat in Leith after McNaughton, 29, lured him there using a fake profile on the hook-up site Gaydar.

In 2023, McNaughton pleaded guilty to the murder and to perverting the course of justice.

We remain horrified that anybody could have treated a vulnerable 75-year-old in such a despicable manner. Our life will never be the same and we will always ask the question, What if?

Black, who was present in the property at the time, was cleared of any involvement in the killing, with the jury returning a not proven verdict on the murder charge.

However, during the trial Black admitted perverting the course of justice by hiding the body and lying to police when they twice visited his flat during their investigation into the missing person.

Following the murder, the pair hid Mr Coshan’s body under the bed while they went to a fun fair at Burntisland in Fife, and they kept it hidden for days while they went on a spending spree with Mr Coshan’s bank cards.

On around August 15, they put the pensioner’s body in a stolen suitcase and drove it to a layby on the A696 between Otterburn and Belsay in Northumberland, where they tried to dig a grave before dumping the body next to a wall.

A jury at Edinburgh High Court cleared Black of murder but unanimously found him guilty of perverting the course of justice.

Black, dressed in a white T-shirt and blue jacket, showed no reaction as the not proven verdict on the murder charge was read out.

Judge Lord Scott told Black: “You have been found guilty of attempting to defeat the ends of justice which, as (defence advocate) Mr Lenehan rightly says, is an extremely serious matter.”

He said that a “significant period of custody will follow”, and indicated that similar cases had attracted prison sentences of up to six years.

In a statement issued through police, Mr Coshan’s family thanked those who have supported them.

They said: “Their continued support has, without doubt, helped us through this nightmare and has been an amazing display of the best of human nature.

“This is in stark contrast to the worst of human nature, which was displayed by the individual who took Peter’s life.

“We remain horrified that anybody could have treated a vulnerable 75-year-old in such a despicable manner.

“Our life will never be the same and we will always ask the question, ‘What if?’

“There is, of course, no answer to ‘What if’, as events have overtaken us and there is no going back in time.

“However, we have happy memories of Peter and can reflect on the positive impact he had on so many people’s lives.”

Tony Lenehan KC had earlier said that perverting course of justice was a “serious crime, which will inevitably be visited with a considerable period in custody”.

Earlier, the court heard that since meeting Mr Coshan on Gaydar in about August 2021, McNaughton stole tens of thousands of pounds from him after gaining access to his bank accounts, and that Black had been aware of this from the start.

This included £38,000 in September 2021 which, McNaughton said, the pair used to pay for a trip to Blackpool, and a further £32,000 in June the following year.

McNaughton told the court that when Mr Coshan found out about the theft, he threatened to tell the police unless he received free sexual favours for a year, and claimed they hatched a plan to kill the pensioner after he became “fed up” with providing sexual favours without getting anything in return.

The jury cleared Black of any involvement in the killing.

Lord Scott said that Black and McNaughton will both be sentenced on June 17.

Police Scotland Detective Superintendent Andrew Patrick, senior investigating officer, said: “This was a horrendous crime which has left Dr Coshan’s family absolutely devastated and our thoughts remain with them at this difficult time.”