Indeed, doubt has now been cast over the entire events of 8 September 1986 and the months running up to the publication of a story linking him with Monica Coghlan, a prostitute.
The most crucial issue, which underpinned the original libel trial, is who Jeffrey Archer really was with that night.
The setting for the mystery is Le Caprice, a London restaurant favoured by the rich and famous. The owners at the time, Christopher Corbin and Jeremy King, had a reputation for making it their business to know what happened in their clients' lives. They were also known for their discretion. The pair were subpoenaed to appear at the libel trial but never called.
Friends now say their evidence would have confirmed that Lord Archer was at the restaurant that night. But 8 September was busy and they would have been too preoccupied to notice what time he left.
Lord Archer's dinner partners that night were his literary agent Richard Cohen and his wife Caroline but they only provided an alibi until 10.30pm, when they left him at the restaurant.
According to Lord Archer's version of events, he was with his friend Terence Baker until 1.15am on 9 September. This was confirmed by Mr Baker who said he had drinks at the bar with Lord Archer before the then Tory deputy chairman drove him to his home in Camberwell, in south London.
It was during this time that Aziz Kurtha, a solicitor, falsely claimed that Lord Archer was not with Terence Baker.
His evidence stated that he saw Lord Archer waiting to meet Ms Coghlan, the prostitute who also gave false evidence stating she had sex with him.
She falsely stated that Lord Archer was in fact with her until 12.45am on 9 September at a hotel within walking distance of Le Caprice.
Mr Kurtha is now understood to run a law practice based in Dubai, in the United Arab Emirates. He told his story to a journalist from Private Eye but never asked for money.
Another remaining puzzle is why Lord Archer was unable to give a consistent account of when he first discovered there were rumours circulating about him and Ms Coghlan. In fact, he gave 27 different versions of the timing.
There is also confusion as to why he wrote in his office diary that he spent the evening of 9 September with Mr Baker. This conflicts with his current version of events which states that he spent that evening with a lady whose identity he wanted to protect.
Mr Baker is the one person who could account for those crucial hours after Lord Archer finished dinner and confirm whether he is now telling the truth about the following evening. He is also the one person who is unable to give any answers. The theatrical agent died suddenly at the age of 52, four years after the libel trial.
Last week, Valerie, his widow, would only tell reporters who came knocking at her door in South West London that she does not remember the events of that night and that her husband never discussed the case with her.
The truth may never be revealed as dead men have never been known to tell tales.