The wife of a fire chief has revealed how she turned detective to get him freed from jail after he was falsely accused of raping a 14-year-old boy in the 1970s.

Lynn Bryant, of Dorset, was devastated when her husband David, 66, was jailed for eight and a half years after the alleged victim Daniel Day sent him a sinister letter that read, 'you will pay for what you've done' and made the claims.

Mrs Bryant, 53, assembled a team of lawyers and private investigators to show that Mr Day was a chronic liar who had sought medical help for his condition - leading to Mr Bryant's conviction being quashed this week.

Mr Day, now aged 53 and living in Bromley, Kent, accused Mr Bryant, then a decorated fire chief, of raping him at the local fire station 35 years earlier.

Lynn Bryant, of Dorset, has revealed how she turned detective to get her husband David Bryant (both pictured left) freed from jail after he was falsely accused of raping a 14-year-old boy, Daniel Day (right), now 53, in the 1970s

He claimed Mr Bryant carried out the attack with another fireman in Christchurch, where Mr day grew up, after they had invited the schoolboy to their fire station to play darts.

Mr Day, who worked as a bottle washer at a bar in Christchurch where firemen would regularly drink, claimed he had been raped on an unspecified date between 1976 and 1978.

He sent the Bryants a letter in 2012, in which he said he would be going to the press and police to report what Mr Bryant 'had done' 35 years ago.

It read: 'Dave, its Danny Day. 35 yrs ago I used to collect the glasses in the Legion and I am the same one that you ... played darts with in the fire station (remember!)

'At 6 o'clock tonight, I am going to the police station to report what went on and at 7 to the national papers. I think it is time you and me had a chat.'

The letter concluded: 'One way or another you will pay for what you done.'

Mr Bryant was charged with buggery in 2013, despite his accuser having no corroborating evidence for his claims.

At a Court of Appeal hearing, a judge said Mr Day did not report the alleged incident until 2012 'after being motivated to come forward in the aftermath of the Jimmy Savile affair'.

At the time of the alleged offence Mr Bryant was aged 26. He has been described as a man of 'impeccable character', who has led an 'exemplary' life, not only in his work as a fireman, but in wider work involving charity in the community.

Speaking about the ordeal, Mrs Bryant told the Telegraph: 'We made a conscious decision to stay strong. I continued to fight to get Dave cleared because it was so wrong.'

During the trial police had not obtained the medical records that showed Mr Day had repeatedly sought treatment for being a 'chronic liar' from his GP between 2000 and 2010.

Mrs Bryant also discovered the police had been using old plans for the fire station, showing a different blueprint that did not corroborate Mr Day's claims.

The pool table, where he claimed he was raped, was not purchased until 1992.

Mrs Bryant, of Dorset, was devastated when her husband David, 66, was jailed for eight and a half years after the alleged victim Daniel Day sent him a sinister letter that read, 'you will pay for what you've done' and made the claims

But Mr Bryant was found guilty of sexual assault by a majority verdict in December 2013, and jailed for six years in January 2014.

Mrs Bryant, who went to school with Mr Day, said: 'Danny Day is an evil man. He was after the money.'

The Bryants believe Mr Day made the claims to extort money, and is believed to have received around £50,000 as a victim of crime thanks to the Criminal Injuries Compensation Scheme - which is tax-payer funded.

Prosecutors had made a £200,000 civil claim against the Bryants and Dorset County Council.

Mr Day began civil action, claiming aggravated damages because he said he couldn't further his career as a champion boxer due to the mental strain.

But Mrs Bryant's investigators revealed his claims - that he had quit the British boxing team at the 1984 Los Angeles Olympics for fear Mr Bryant would recognise him on TV - were lies.

Lawyers also discovered Mr Day had a history of mental illness after obtaining his medical records.

Mr Day had written a witness statement backing up his claims of a boxing career, which was signed by a friend - who admitted that the claims were false.

Mrs Bryant, 53, assembled a team of lawyers and private investigators to show that Mr Day was a chronic liar who had sought medical help for his condition - leading to Mr Bryant's conviction being quashed at the Royal Courts of Justice (pictured), London, where the judge said they 'regret' that Mr Bryant suffered the consequences that he did

As a result, the Bryants want Mr Day and his friend to be investigated for perverting the course of justice or for perjury.

Mr Bryant said Dorset police had not done a 'proper job' of investigating the claims.

A spokesman for Dorset police said: 'Dorset Police takes allegations of this nature very seriously and conducted a very thorough and detailed investigation.

'The findings of the investigation were passed on to the Crown Prosecution Service who chose to prosecute.

'We are yet to receive formal notification of the ruling from the Court of Appeal. When this is received we will consider the findings in full.'

Mr Justice Singh, announced the decision to quash the conviction at the Court of Appeal in London for the ruling earlier in the week.

He said that the one issue in the case was 'credibility', adding: 'This was vital to the jury's task of resolving the conflict in the evidence between the complainant and the appellant.'