A mother and son who murdered a runner in a dispute over the use of a footpath have been jailed for life.
Carol Dawson, 72, and Scott Dawson, 41, targeted Gary Dean because he took a route across their land to go running, Sheffield Crown Court heard.
His body was found in a ditch near his home in Barnsley in September 2018. He had been shot in the back with an air rifle and beaten with rocks.
Judge Jeremy Richardson told them they “fed off the venom within each other”.
Sentencing the son to a minimum of 31 years and the mother to at least 26 years, he said it was “a toxic mixture [that] led to murder”.
The judge said the pair had carried out the killing in “wicked and cruel” fashion.
He said the murder was worsened by 48-year-old Mr Dean’s autism, which made him a vulnerable target.
During a five-week trial, jurors heard the Dawsons, both from Barnsley, were involved in a long-running and bitter feud with Mr Dean, who regularly used the route across their land.
He tried to escape by crawling along a ditch during the attack on 6 September, the court heard.
Scott Dawson, of Allotts Court, and Carol Dawson, of Stonewood Grove, had intended to dispose of his body by using a digger but were prevented from doing so when Mr Dean’s body was discovered by a walker.
His wife, Caroline, a head teacher, described him as being obsessive about running and trains and was “quite autistic in his nature”.
She explained to jurors how she and her husband were regularly followed and threatened, describing how four youths burst into their home on Silkstone Common, injuring both of them.
The school where she worked once received a letter claiming she should not be allowed to work with children as Mr Dean had attempted to lure youngsters into the woods with him.
But a local authority safeguarding inquiry found nothing to support the allegation and her husband was never arrested, the court heard.
Amid the dispute, the Dawsons tried to secure a restraining order against Mr Dean after complaining to police about him, saying he was damaging their property, and a “stay away” sign had been erected, jurors heard.
In a statement, Mrs Dean previously said she had had to “come to terms with the fact that my husband suffered a painful and violent death and that he died alone in a ditch”.
“The brutal nature of Gary’s death haunts us all,” she said.
“I cannot begin to imagine the pain and terror he felt as he was beaten to death.”