The former wife of Colin Howell who told police in Northern Ireland she kept his double murder a secret for over a decade will not be prosecuted.
When Kyle Jorgensen, an American, and Howell were married he told her how he gassed his first wife, Lesley, as well as Trevor Buchanan, the husband of his lover Hazel Stewart.
He persuaded Ms Jorgensen not to inform the authorities for the sake of their children.
Howell is the father of ten children.
After Howell was charged with the two murders Ms Jorgensen returned to Florida with their five children and filed for divorce.
The Northern Ireland Public Prosecution Service said Ms Jorgensen would not be prosecuted as there was insufficient evidence to provide a reasonable prospect of conviction.
For almost 20 years it was believed Lesley Howell and Trevor Buchanan had taken their own lives after their bodies were found in a car at Castlerock, Derry, in May 1991.
However, the truth about what happened to the RUC officer and Mrs Howell, a mother-of-four, only emerged in 2009 when Colin Howell confessed to police that he had murdered them and staged their deaths to look like a double suicide.
In 2010 Howell, a dentist, was jailed for a minimum of 21 years. He was sentenced to life imprisonment after pleading guilty to poisoning his wife and ex-lover's husband.
In 1991, the bodies of Colin Howell’s wife Lesley, aged 31, and RUC constable Trevor Buchanan, who was 32, were found in a car filled with exhaust fumes. It was concluded at the time that the couple had died in a suicide pact.
Constable Buchanan's wife Hazel was having an affair with Colin Howell.
She later married former police Chief Superintendent David Stewart.
During Howell's trial the judge said the couple were murdered because Howell saw them standing in the way of his adulterous desire to be with Hazel Stewart.
She was sentenced to life in 2011 and is serving a minimum of 18 years in prison.
