The then Home Secretary Michael Howard was allegedly tricked
A former underworld armourer accused of supplying guns to a gang of Liverpool criminals told a court he had been coerced into giving a false statement.
Arthur Shaw was giving evidence at Southwark Crown Court at the trial of John Haase, 59, and Paul Bennett, 44.
The pair, who deny conspiracy to pervert the course of justice, allegedly obtained guns from Shaw and then planted them across Merseyside.
Haase and Bennett were freed after getting a Royal Prerogative of Mercy.
In 1995 they were sentenced in open court to 18 years in prison for supplying heroin but walked free a year later after a deal agreed by the trial judge and signed off by the then Home Secretary Michael Howard.
The latest trial has heard the judge recommended the deal because of a report by Haase's Customs handler, Paul Cook, which suggested Haase had tipped off the authorities about 28 caches of guns across the North West, including a gun at Strangeways prison in Manchester.
But Gibson Grenfell QC, prosecuting, said the seizures were bogus as the weapons had been planted by Haase's and Bennett's associates.
The Crown claims the majority of the guns were supplied by Shaw, who reactivated a number of weapons and sold them to Haase's associate, Tony Ambrose.
But Shaw, who was jailed for 10 years in 1996 for supplying guns and ammunition, stepped into the witness box on Thursday and told the court he had been nearing the end of his sentence in Sudbury open prison in Derbyshire when he was visited by two police officers.
Shaw, who had a workshop in Wigan, said the officers were from Derbyshire and told him they were investigating William Greenwood and his son Mitchell, who were suspected of selling hundreds of guns.
Cross-examined by Trevor Burke QC, for Haase, Shaw said: "They said 'you're expecting parole are you?' and I said I was because I had done all the courses and my wife had had a nervous breakdown. But they said 'that depends on us'."
He said: "They said they had trawled all the prisons in England looking for someone like me who would fill in the blanks."
Shaw claimed he was forced to make a statement incriminating the Greenwoods and also Mr Ambrose and then gave evidence at the trial of the two men, who were later convicted.
Mr Burke said: "So what you told police about Ambrose can't be true?"
"No, I was under pressure," he replied.
"Did you get parole?" asked Mr Burke.
"Yes. I got a letter from the Chief Constable of Derbyshire recommending me for parole," he replied.
'I was terrified'
Mr Grenfell then asked him: "When you were giving evidence you were out of prison by then, did you ever say then that none of this is true: it was forced out of me by threats and promises?"
"No, I was still so terrified. The police came to see me four times and they said my parole could be snapped back," Shaw replied.
"Did you ever make a complaint?" Mr Grenfell asked.
"I daren't," he replied.
Earlier the trial heard from retired detective Sue Harrop, who was working on the Dedicated Drugs Unit of the North West Regional Crime Squad in the mid-1990s.
She said they often received information from Mr Cook about guns but did not initially realise it came from Haase.
Mrs Harrop said: "Originally it was a good result. There was a lot of gun crime in the area and any recovery had to be a good thing.
"It certainly brought kudos to our unit but as time went on the unit became less enamoured of this work."
She said they felt the guns were "disingenuous" and suspicious because nobody was ever arrested in connection with them.
Haase's wife Deborah, 37, and another woman, Sharon Knowles, 36, both from Merseyside, also deny perverting the course of justice.
Mrs Haase also denies the possession of firearms and ammunition without authority.
Mr Ambrose has denied perverting the course of justice and is due to face trial separately.
The trial continues.