GDP who staged a double suicide is jailed for at least 21 years

The full details of how dentist Colin Howell staged a double suicide after murdering his wife and his mistress's husband have come to light following his conviction.

Howell pleaded guilty to the murders of Lesley Howell, 31, and Trevor Buchanan, 32, at their homes in May 1991. In December he was sentenced to a minimum of 21 years in prison at Belfast Crown Court.

At a pre-sentence hearing, the court heard how he drugged both victims with temazepam before attaching part of a baby's feeding bottle to a garden hose in order to poison them with carbon monoxide fumes from a car. Judge Mr Justice Hart explained how each murder was carried out while the victims were asleep and defenceless in their own homes, Mrs Howell on the sofa and Mr Buchanan in his bed.

The bodies of both victims were later found in a car parked in a garage in Castlerock, Co Antrim, with a later inquest ruling it as suicide. The ruling stood for nearly 20 years until January 2009 when Howell walked into a police station and told officers that God had told him to confess all.

On hearing how Howell carried out the murders and then staged the double suicide – even going as far as placing family pictures next to his wife's body – Crown lawyer Kieran Murphy told Mr Justice Hart: "This was a meticulous and devious plan, premeditated in a manner that might be described as professional."

He continued by saying: "The actions of the dentist were calculated, callous, manipulative, evil and wholly without mercy for two defenceless victims, one of whom was his wife and the other the loving husband of his co-accused."

Colin Howell's former lover Hazel Stewart is due to stand trial in February for the two murders. She denies the charges.