“Blood!” cried the policewoman, pointing to the red trail that led down the Dunstable street. A killer was being sought in the town, and this seemed as good a clue as any.

With a Scotland Yard detective sergeant accompanying her, the policewoman followed the trail several hundred yards to a house in Edward Street, and knocked on the door. The young woman who opened it said she didn’t live there. She was looking after the house for a friend who was out. Asked to explain the blood on the doorstep, she said it was red paint. “We’ve had a rather careless painter here this morning,” she laughed.

“But don’t go away,” she added. She said the officers should go to her home in Periwinkle Lane and talk to her 13-year-old daughter. “Before she went to school this morning she said she thought she’d recently witnessed a murder.”

The story of the trail of red paint that was to lead to the arrest of a killer had begun on AUGUST 25th, 1960, with the discovery of the body of Keith Arthur near a farm outhouse. A Dunstable machine-operator, he had died from a single gunshot wound and had been killed elsewhere, said the Home Office pathologist Dr. Francis Camps.

The schoolgirl who told her mother she had seen a murder was interviewed by detectives. She said that on the evening of August 23rd she had been baby-sitting for Jack Day and his wife Margaret at their home in Edward Street. When Mrs. Day came back she asked the girl to pop out to the corner shop for a frozen pork pie. When the girl returned and went into the living-room a man was with Mrs. Day. Moments later Mr. Day came home and asked the man, “What are you doing here?”

“The way he said it, I thought they were going to fight or something,” said the baby-sitter. “Then the man said, ‘I came to see if you would buy me a drink, Jack,’ or something like that. Mr. Day said, ‘This will go with it,’ or something similar, and pulled a gun from his pocket. I heard a bang and saw a flash and then I ran home.”

Taken in for questioning, Jack Day, a 30-year-old car salesman, was found to have blood on his clothes which was of the same group as Keith Arthur’s, and soil on his trousers matched that at the spot where the body was found. The murder weapon was recovered at the garage where he worked.

Admitting the shooting, Day claimed it was an accident. He said that on arriving home, “I took my gun out of my pocket. It was in a handkerchief. I put the gun down on the settee. The next thing I knew the damned thing went off. Keith was sort of standing there. I said, ‘Blimey, sorry it happened.’ He said, ‘It has got me in the throat.’”

Day went on to say that he and Arthur, who was losing blood heavily and could hardly walk, went into Dunstable town centre to find a doctor, but on the way Arthur collapsed, coughing blood. “I got my arm round him and we rushed home.”

Day said he then ran back into the town to get his car, and on his return Arthur was lying in a pool of blood in the kitchen. “I picked him up and took him to put him in the car. He was dead when I got him in the car. I just panicked and I didn’t know what to do. I don’t know how I got him in the car.”

He said he dumped the body where it was found, and expected to see the police already at his home on his return. “The wife told me to give myself up, but I daren’t.”

At his trial the court heard that Day had said that he would shoot any man he found with his wife. Gun experts testified that Keith Arthur had been shot in the throat from a range of only nine inches, and the revolver could not have gone off accidentally. Great trigger pressure was required to fire it.

Convicted of Keith Arthur’s murder, which he continued to deny, Day was sentenced to death but hoped for a reprieve. Three days before his execution date he saw a magazine report that he had already been hanged. He promptly instructed his lawyers to sue the periodical on the grounds that it was libellous to call him a murderer before a decision had been made about a reprieve.

That decision went against him, however, and he was executed at Bedford Prison on March 29th, 1961. “I’m sorry I did it,” he told the hangmen. “I didn’t really want to kill him.”