A CHURCH warden and a magician told a series of lies to try and get away with murdering a university lecturer and plotting to kill a retired headmistress, a court has heard.

Benjamin Field, 28, and Martyn Smith, 32, had been caught out by the "sheer number of lies" they had told, Oliver Saxby QC, prosecuting, suggested.

Field and Smith are accused of murdering Peter Farquhar, 69, and planning to kill Ann Moore-Martin, 83, following a sustained campaign of "gaslighting".

Field has admitted fraudulently being in relationships with Mr Farquhar and Miss Moore-Martin as part of a plot to get them to change their wills.

Prosecutors allege Field and Smith targeted Miss Moore-Martin a few months after allegedly murdering Mr Farquhar in the village of Maids Moreton, Buckinghamshire.

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In his closing speech to the jury at Oxford Crown Court, Mr Saxby said: "There have been some pretty desperate attempts to get away with it.

"Common sense tells you they are guilty."

The barrister accused Field of being motivated by "greed and a willingness to inflict pain and suffering".

"He put it beautifully in that document... promiscuous in the matter of death," he said.

"He is arrogant in the sense that he could get away with it, finding it amusing that he could get away with it."

Mr Saxby said Field and Smith had constructed "fake evidence" to paint Mr Farquhar as an alcoholic who was proving difficult to care for.

"They were not hanging in there to be his mate. They were hanging in there for his money and the prospect of him dying," he said.

"You have the evidence of this in the agreed facts and the read evidence, from his friends who never regarded him as an alcoholic and from the liver specialists who said he did not have any signs of liver disease.

"Will fraud has a short shelf life. The person needs to die for the will fraud to happen."

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Mr Saxby said that for Mr Farquhar to succumb to an alcohol-related death, he would have to be drinking and Field and Smith would have to be there to make sure he drank.

"Obviously they cannot admit giving him alcohol or being there when he died," Mr Saxby said.

"All of this gives rise to this complex cover story that Ben Field came up with, which Martyn Smith has gone along with, which is the stuff of farce.

"Benjamin Field gives Martyn Smith a bottle of whisky, which he leaves behind, and Field leaves it out to catch out Peter Farquhar and he is tempted to drink it. How clever.

"Why didn't Ben Field want to be there to see if Peter Farquhar was caught out? Why didn't Ben Field leave the bottle there himself?

"Because he didn't want the focus to be on himself. Questions would be asked, hence the convoluted story.

"Martyn Smith needed to know what was going on for it to work. His part was an important one - his job was to get the alcohol in there, which later could be passed off as a coincidence.

"An amazing coincidence to happen. But by the same token when people lie and those lies are put together over a two-year period, it is the sheer number of lies that catches them out."

The jury has previously been told the police covertly recorded conversations Field and Smith had while being transported to the magistrates court, in which Field talks about "getting away with it".

"This is a person on the cusp of a dreadful miscarriage of justice. He cannot help himself - his words not mine - 'get away with'," Mr Saxby said.

"They don't mean get off and con a jury. They mean I am not guilty and I will be proven not guilty. It is the sort of convoluted plan that Ben Field would come up with."

He added: "They are guilty on count one."

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Mr Saxby said that after Mr Farquhar's death was ruled alcohol-related by a coroner, Field and Smith would have felt "emboldened" and moved onto Miss Moore-Martin.

He accused Field of planning her death in several different ways, such as during sex, a heart attack or suicide.

"This was all down to the dismantling of the individual that Ben Field achieved with her and Peter Farquhar," he said.

"It is for greed, it is power greed, being clever greed - being the person that can carry it off."

Mr Saxby said it was "pushing incredulity to breaking point" to suggest, as Field had, that Smith had not known about the deception of the spinster.

He also dismissed suggestions from Field that his younger brother Tom, 24, and Smith had been his "unwitting dupes" in the dialysis fraud.

Field and Smith deny charges of murder, conspiracy to murder and possession of an article for the use in fraud.

Field, of Wellingborough Road, Olney, Buckinghamshire, also denies an alternative charge of attempted murder. But he has admitted four charges of fraud and two of burglary.

In addition Smith, of Penhalvean, Redruth, Cornwall, denies two charges of fraud and one of burglary.

Cambridge University graduate Tom Field, also of Wellingborough Road, Olney, is on trial accused of a single charge of fraud.

The trial was adjourned until Wednesday.