ONE murder, three versions of the story.

A gunshot ends the life of flamboyant farmer Maxwell Robert Garvie on a May night in 1968. Three people are accused of the crime - his wife, Sheila; Brian Tevendale, his wife’s lover; and Alan Peters, a young man whom Max had never met.

Glasgow Times: Sheila Garvie and Brian Tevendale

The three versions of what happened are almost entirely contradictory, with just about the only common detail being that Max is dead. In court, Sheila Garvie and Brian Tevendale are found guilty, and Alan Peters walks after a not proven verdict.

Now, Sheila Garvie: Mastermind or Victim, a book based on the story by former Glasgow prosecutor Allan Nicol, throws new light on the trial, and asks whether Sheila really was a cold murderer, or a woman driven to the brink after years of abuse and torment.

Glasgow Times: Sheila Garvie: Mastermind or Victim

The trial was one of the most famous and salacious in Scottish court history. A mesmerised nation followed avidly, as details of nudist weekends, wife-swapping, drug and alcohol abuse and more were revealed in the newspapers.

Glasgow Times: Allan Nicol

Allan, who was an Advocate Depute, prosecuting in High Courts throughout Scotland before retiring and beginning a writing career, explains: “Having spent all of my working life immersed in Scottish criminal law, I naturally gravitate to reading about cases from the past, some more high profile than others.

“Two of the more infamous I have previously focused on involved serial killers Peter Manuel and Archibald Hall. Both were ruthless psychopaths who killed without compunction for their own personal gratification.

“Sheila Garvie, on the other hand, was a gentle mother of three who had lived a blameless life up until her husband Max chose to join in what he imagined were the Swinging Sixties. I wanted to fully understand the basis of her conviction for murder and expected to emerge at the other end of the process convinced that justice had been served.”

He pauses. “Now, I’m not so sure.”

Sheila was charged with murdering her husband by police officers who initially believed her lover’s story that she had shot and killed Max and he,Tevendale, had only helped dispose of the body.

When it became clear that Tevendale was the killer, the prosecution case evolved into proving her guilt by her failure to somehow intervene in the assault on her husband, then doing nothing to bring Tevendale to justice before the three accused were arrested.

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“Sheila Garvie undoubtedly told lies and covered up for Tevendale after he killed Max,” he adds. “I was interested in how the prosecution approached the case against her. Should she have done more to stop her husband’s execution? In studying the case, it became clear, however, that the evidence given by Tevendale’s sister, Trudy, and Sheila Garvie’s co-accused, Alan Peters, unexpectedly bolstered the Crown case in suspicious ways. Ever since the trial, there have been questions asked about the verdict. Sheila wrote a book in 1980 about her life with Max and the events leading up to his murder and she continued to maintain her innocence.

“Perhaps now, after all these years, the truth is beginning to emerge.”

Sheila Garvie: Mastermind or Victim (Ringwood Publishing) is out now.