“I have strangled a girl,” Kenneth Roberts told police called to his home in Scunthorpe in the early hours of MAY 11th, 1955. He had arrived home at about 12.25 a.m., and had confessed the killing when his wife asked where he had been.

He now led officers to a timber yard on the town’s outskirts, where they found the body of Mary Roberts, to whom he was not related. She was an 18-year-old unmarried mother and was believed to be a prostitute.

Charged with murder, the 24-year-old warehouseman pleaded not guilty when he appeared at Nottinghamshire Assizes. Seeking a manslaughter verdict, his counsel submitted a convoluted argument in which he claimed that his client could not be guilty of murder because when he strangled Mary he thought she was already dead.

“He placed his hands on her throat and throttled the girl until her heart stopped beating,” the defence counsel told the jury. “He panicked and then made a half-hearted attempt to conceal what he had done. Thinking, as he must have done, that the girl was dead, he tied a scarf round her neck when she was to him a lifeless corpse. For just a few moments before he did that he felt her heart stop beating. Had he left her then she would still be alive today.

“My submission is that even if you are satisfied that he intended to murder the girl, and that when he had his hands on her throat he attempted to do so, he must have thought when her heart stopped beating that she was dead and what he did afterwards is not, in my submission, therefore murder.”

Unimpressed but doubtless bewildered, the jury convicted Roberts of murder and he was hanged on July 12th, 1955.