Leeds Crown Court was told that David Howells, 48, had never discussed ways to get rid of his wife, Eve, also 48, with his sons Glenn and John, and was "horrified" when he discovered that Glenn had killed her and John had got rid of the weapon and blood-soaked clothes.
Mrs Howells's skull was shattered when she was attacked with a hammer in the living room of the family home in Huddersfield, West Yorkshire, in August 1995. Mr Howells, and his sons Glenn, 17, and John, 15, deny murder. Glenn admits manslaughter on the grounds of provocation.
John told the court on Wednesday that although his father was playing darts two miles away when his wife died, he had been involved in plans to kill her for up to a year before her death. But Mr Howells, who admitted that he had failed to protect the boys when their mother ill treated them, said that although Glenn once mentioned getting rid of his mother, he thought it was a bit of "nonsense".
He said: "I think he'd been upset with her. I didn't believe what I was hearing. I tried to make as light of it as I could and treated it as a bit of nonsense."
And he added: "I did not get my children to do my dirty work."
Mr Howells told the court that although he knew his sons hated their mother, the first he knew of their part in her death was when he heard them talking in the days after the killing - which police initially thought was a bungled burglary. "I could tell something had happened, so I just listened and waited until I heard more," he said. "I learnt that somehow they were involved in what had happened to my wife - that they had something to do with the killing."
He said it was Glenn who eventually confessed, saying: "I'd just had enough, dad. I had to do something about it. I'm sorry, I didn't mean to, I just had to."
Stephen Hawksworth, for the defence, asked Mr Howells whether he considered going to the police when he knew his sons were involved. He replied: "I was left with no option but to try to help them the best way I could. I just offered my help."
When asked why he helped them, he said: "Because they were my sons."
Mr Howells was arrested a month after his sons after covert tapes made as he visited them in custody pointed to his involvement. But he told the court that anything he said in the tapes was just part of helping them after he realised what they had done. The trial continues.Reuse content