A former church warden serving a life sentence for killing a university lecturer following a campaign of physical and mental torture has launched a fresh bid to challenge his conviction.

Benjamin Field, 31, was found guilty of killing Peter Farquhar, 69, in order to inherit his house and money after driving him to think he was losing his mind following a period of gaslighting.

The prosecution case at trial was that Field secretly gave Mr Farquhar drugs and spiked his whisky, hoping that his eventual death at his hands would look like suicide or an accident.

Field, of Wellingborough Road, Olney, Buckinghamshire, was ordered to serve at least 36 years behind bars in October 2019 after being convicted of Mr Farquhar's murder following a trial at Oxford Crown Court.

Benjamin Fields police mugshot Pictures: PA/TVP

Benjamin Field's police mugshot Pictures: PA/TVP

The Court of Appeal dismissed a challenge by Field against his conviction last year, and he was refused permission to take his case to the Supreme Court.

He is now attempting to reopen the appeal, with his lawyers arguing that the Court of Appeal's judgment was flawed.

READ MORE: Church warden Benjamin Field jailed for life for murdering Peter Farquhar

David Jeremy QC argued at the appeal last year that the trial judge, Mr Justice Sweeney, misdirected the jury as to the "chain of causation" involved in Mr Farquhar's death - in particular whether he had been "tricked" by Field into drinking the whisky, or had done so out of choice.

At a hearing in London on Thursday, Mr Jeremy argued the Court of Appeal was unable to make a finding that Mr Farquhar's act of drinking the whisky "was not autonomous", which would have justified the trial judge's directions.

He told a different panel of the Court of Appeal, led by Dame Victoria Sharp: "Unable to make that finding, the court ought to have allowed the appeal, but instead it dismissed it."

Mr Jeremy told the court at the appeal hearing last year that the directions given to the jury before it started its deliberations left the defence with "nothing to say" when in fact there was "much that could be said on Field's behalf on the issue of causation".

READ MORE: ‘Thoroughly evil’ church warden launches appeal over murder conviction

He said full directions would have explained to jurors the fact that the prosecution "could not prove causation" because there was "no evidence that Mr Farquhar had been forced or tricked" into consuming alcohol and a tranquiliser drug.

Psychiatrists told the court Benjamin Field was either suffering from a narcissistic personality disorder or a psychopathic personality disorder (Thames Valley Police/PA)

Psychiatrists told the court Benjamin Field was either suffering from a narcissistic personality disorder or a psychopathic personality disorder (Thames Valley Police/PA)

Oliver Saxby QC, who represented the Crown Prosecution Service, said at that hearing that the drugs, alcohol and "smothering" were all part of a plan concocted by Field.

Field's crime came to light after he began targeting Mr Farquhar's neighbour, Ann Moore-Martin, in the village of Maids Moreton, Buckinghamshire.

The sexually promiscuous Field also manipulated Miss Moore-Martin, a deeply religious retired head teacher, by writing messages on her mirrors purporting to be from God.

He admitted fraudulently being in relationships with the pensioners as part of his plan to get them to change their wills.

Mr Farquhar, who was torn about his sexuality because of his religion, died in October 2015 while Miss Moore-Martin died in May 2017 from natural causes.

Church warden Benjamin Field admitted being in a fraudulent relationship with Ann-Moore Martin (Thames Valley Police/PA)

Church warden Benjamin Field admitted being in a fraudulent relationship with Ann-Moore Martin (Thames Valley Police/PA)

Field underwent a "betrothal" ceremony with gay Mr Farquhar while also having a string of girlfriends and was in a sexual relationship with Miss Moore-Martin, who was 57 years his senior.

Miss Moore-Martin gave him £4,000 to buy a car and £27,000 for a dialysis machine.

READ MORE: Ex-church warden to appeal against conviction for murder of university lecturer

Field admitted two counts of burglary and three of fraud before his trial for murder.

He was found not guilty of conspiracy to murder Miss Moore-Martin and an alternative charge of attempted murder. He was also found not guilty of possession of an article for use in fraud.

Two psychiatrists said Field was either suffering from a narcissistic personality disorder or a psychopathic personality disorder.

Sentencing Field, Mr Justice Sweeney said he "lived by deception and deceit and had been a well-practised and able liar".

University lecturer Peter Farquhar was killed by Benjamin Field (Thames Valley Police/PA)

University lecturer Peter Farquhar was killed by Benjamin Field (Thames Valley Police/PA)

"You further admitted how you could manipulate and manoeuvre people, however sceptical they may have been, to achieve your ends without ever asking them to do so directly," he said.

The judge said that Field murdered Mr Farquhar by covertly giving him drugs and getting him to drink strong whisky and then, "if it was necessary, finished him off by suffocating him in a way that left no trace".

Dame Victoria, who heard Field's bid to reopen the appeal with two other judges, said they will give their ruling at a later date.

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