“Following expert evidence from a psychiatrist it was suggested that no useful purpose would be served by Mr Thomas being detained and treated in a psychiatric hospital, which would be the consequence of a special verdict in this case.

“It is now clear that the psychiatrists feel the risk of reoccurrence is very, very small. It is only because of highly sophisticated tests carried out by sleep experts that Mr Thomas’s condition could be confirmed.”

Judge Mr Justice Nigel Davis told Thomas that although he would feel guilty about killing his wife: “In the eyes of the law you bear no responsibility for what happened.”