Dr. Jeffrey MacDonald
The man Helena implicated in the murders Greg Mitchell was a seriously screwed up, drug-addicted soldier of nineteen when he came back to Fort Bragg from his tour of Vietnam. Right after the MacDonald murders, he did what very few soldiers did, he asked to be sent back to Southeast Asia.
While he was waiting to be shipped back, he had an argument with his mother which upset her terribly. Greg had yelled at her that he had to go kill all the ten-year-olds he could find. Shortly afterwards, he overdosed on heroin and was finally sent back to Vietnam until the Army discharged him for drug addiction in 1971.
When he got back to Fayetteville, he broke down emotionally and confessed that he had murdered people and begged God to forgive him. Later on, he was seen near a farmhouse that had the words "I KILLED MACDONALD'S WIFE AND CHILDREN" freshly painted on the interior wall.
Subsequently, he admitted to friends that he was worried because the FBI was interrogating him about the MacDonald murders. He confessed to one of them that he was guilty.
Other evidence ties Greg Mitchell to the crime scene. Forensic experts believed that Colette had been killed by a left-handed person. Mitchell was left-handed, whereas MacDonald is right-handed. Mitchell had Type O blood the likely blood type on Colette's hands. MacDonald has Type B blood, which was not found on Colette's hands. Greg Mitchell had brown hair the color of the hair under the victims' fingernails. MacDonald's hair is blond.
Like Helena Stoeckley, his drug dependency caught up with him at a very early age: Greg died in June of 1982 at the age of thirty two from liver disease.