A village shopkeeper bludgeoned his unfaithful wife to death then pretended their post office had been robbed, a jury heard.

Robin Garbutt, formerly of Huby and York, was struggling with credit-card debts of £30,000 and had been taking money from the post office when he snapped and hit Diana, 40, with a metal bar as she slept, Teesside Crown Court was told.

The jury heard Mrs Garbutt, who grew up and went to school near Selby, told her husband she had sex with another man at a party in York in 2008, while Garbutt was sleeping upstairs, and had also chatted sexually on the Facebook website with another man.

Garbutt, 45, told police he was held up at gunpoint by an intruder in the shop in Melsonby, near Richmond, at about 8.30am on March 23, last year, and forced to open the safe. He said he then went upstairs and found his wife battered to death.

But David Hatton QC, prosecuting, said Garbutt murdered his wife, a charge he denies.

He said Garbutt hit his wife on the head with a metal bar three times between 2.30am and 4.30am on March 23, then opened the safe and phoned police.

Mrs Garbutt grew up in Eggborough before attending Brayton High School and Selby College, and lived with her husband in York before they moved to Melsonby to take over the post office.

Mr Hatton said: “Behind the facade of a happy and financially comfortable couple there were problems and all was not as it might have appeared.”

He said that as well as sleeping with a man at the 2008 party, Mrs Garbutt had also kissed a cousin’s husband at a family party and written a note suggesting a sexual relationship had happened.

Mr Hatton said Mrs Garbutt used internet dating sites and had a flirtatious Facebook friendship with a local man with whom she went for late-night bike rides when her husband was asleep.

She told the man her husband “wasn’t into sex” and they were going to see a therapist, the court heard.

Mr Hatton added: “Their conversations on Facebook would have a sexual tone, telling each other what they would like to do to each other if they were alone together.”

The night before she died, Garbutt tried to buy £850 of stock from a cash and carry but the transaction was refused and the bank rang his wife.

Mr Hatton said: “The perception of the Melsonby villagers of a rosy and loving relationship was, say the prosecution, far from the full picture.

“Here was a man with increasing debt desperately trying not to outwardly fail in his business or his marriage.”

Melsonby villager Martha Cheeseman said she saw every window at the post office lit up just before 10pm on March 22 and fellow villager Katherine Googe said that shortly after 10pm, she saw Garbutt walking across the village green with a bag.

Mr Hatton said: “The prosecution contend there was a welling of tension, pressure and ill-feeling. Where could he go? He had nothing.

“He returned. The pressure, tension and ill-feeling erupted in extreme violence in which he killed his wife.”

“There were no intruders in that village post office at that very busy time that spring morning. The defendant killed his wife in the early hours.”

The night before, the couple ate fish and chips about 8.30pm and analysis showed Mrs Garbutt’s digestion stopped, with death, about six to eight hours later, the court heard.

Mr Hatton said police and paramedics found Mrs Garbutt’s body in her bed. Rigor mortis had set in, and they detected hypostasis – blood pooling in tissue after the heart had stopped.

Mr Hatton told jurors: “One of the questions you will have to consider, if you accept this evidence, is the likelihood of a robber or robbers being prepared to violently kill a female sleeping in her own bed - at all - but then, having done so, to wait for four to six hours before going downstairs to rob the post office.

“And then, it has to be said, having been prepared to bludgeon the lady to death upstairs and wait for that length of time, to leave the defendant himself unharmed and unrestrained to raise the alarm.”

Garbutt, of East Road, Melsonby, reported a £10,000 robbery at the post office almost exactly a year before, the court heard, but no witnesses saw anything and no arrests were made.

Mr Hatton said the shop provided a “relatively modest income” and said: “An audit of the accounts has revealed large sums of cash were being transferred into the defendant’s current account, posted by special delivery.

“Notwithstanding that, it was still overdrawn. Where was this cash coming from?” He said any significant discrepancy in the cash holdings would have come to light as a relief postmistress was due to cover for the couple while they went on holiday to the US.

The trial, expected to last four weeks, continues.