The Court of Appeal quashed the convictions of Susan Whybrow, 52, and Dennis Saunders, 57, a flying instructor, who were freed on bail pending retrial at the Old Bailey.
In 1991, Whybrow was jailed for eight years and Saunders given 10 years at Norwich Crown Court for allegedly conspiring to kill Christopher Whybrow, from whom she is now divorced, to gain control of his estate at Leavenheath, Suffolk, and an inheritance of pounds 400,000.
Ordering a retrial on London as soon as possible, Lord Taylor, the Lord Chief Justice, sitting with Mr Justice French and Mr Justice Pill, said that they would give their reasons in full at a later date.
At the appeal hearing, lawyers for the couple argued that the convictions were unsafe because the judge at their original trial, Mr Justice Ian Kennedy, robbed them of a fair hearing by taking on the role of the prosecution and intervening during their evidence with hostility, sarcasm and 'naked mockery'. Their lawyers urged the court to quash the convictions. They said that a retrial could not be held because of the length of time since the alleged events and the wide publicity surrounding the case.
During the six-day trial, it was alleged by the Crown that the lovers, who met when Whybrow took flying lessons, had planned to kill Mr Whybrow but make his death appear as an accident by tipping him and his ride-on lawnmower into a duck pond, giving the impression that he had driven into the pool by mistake. The alleged plot, described as 'one of the most bizarre and hare-brained schemes imaginable', failed when Mr Whybrow escaped and swam across the pond to safety.
The couple denied conspiracy to murder but admitted kidnapping and conspiring to cause actual bodily harm, claiming that they were trying to teach Mr Whybrow a lesson because of his alleged cruelty to his wife.
Yesterday's bail order carries conditions of residence for both - Whybrow at her mother's home in Plymouth, and Saunders at his address in Colchester, Essex. They were ordered to surrender their passports and Saunders must surrender his flying licence.