Colin Howell bragged how he fooled police for over 18 years as he confessed to murdering his wife and lover's husband, Coleraine Crown Court has been told.
The dentist boasted about the 'clever' way he had poisoned Lesley Howell and Trevor Buchanan and made it look like suicide, as he spoke to elders in his church.
Mr Howell's second wife Kyle, who has since filed for divorce, called three senior members of his Barn Fellowship church on a January morning two years ago to say he had made a shocking admission to her and that she wanted them to come round to hear it.
One of the elders - Graham Stirling - said Colin Howell recounted in great detail how he had killed his two victims and then staged the scene in a fume filled garage in Castlerock in May 1991.
'I think there was an element of bravado about his endeavour to hoodwink the police,' Mr Stirling said as he took the stand in the trial of Mr Buchanan's widow Hazel Stewart.
The court was told that in his statement to police hours after he heard the confession, Mr Stirling said: 'I shivered about him bragging he was so clever to fool the police.'
William Patterson, another elder in the Barn Fellowship, which Howell joined only months after the murders, having left Coleraine Baptist church, told the jury how Howell also recounted Stewart's alleged part in the plot.
The dentist killed his wife in the family home by gassing her with carbon monoxide from a hose pipe connected to his car and then did the same to Mr Buchanan at his house.
Mr Howell told police that Stewart drugged her husband so he would be able to overpower him if there was a struggle.
Mr Patterson said this was also the version of events the dentist gave to him and the other two church members.
'He did indicate there was an arrangement that drugs were to be administered to Trevor Buchanan in some food,' he said.
The elder added that Howell claimed the sedatives were put in tuna fish sandwiches.
Colin Howell had moved out of the family home in the period before his confession and was living in a caravan in Castlerock.
He was not at the house when the three elders arrived as he had gone to leave three of his children at school. Before going to meet the elders he called off at the caravan and packed a bag of clothes.
Mr Patterson said he finally arrived at the house holding the yellow bag. 'We were given to understand the packed bag was because he knew the consequences and police would be involved,' he said.
Mr Patterson said the dentist was very agitated at first but his disposition changed during what would be an hour long confession.
