Still GB's best sprinter, Chambers remains banned from the Olympics
Dwain Chambers has announced his intention to secure a place in the British team for the Beijing Olympics.
The sprinter returned to athletics from a two-year suspension for doping in 2005 but remains banned for life by the British Olympic Association (BOA).
By-law 25 has been on the BOA's statute book since 1992 when it decided Britain must get tough with drugs cheats.
The BOA is the only national Olympic committee to maintain this stance but says it will "vigorously" defend it.
"We can confirm that Dwain Chambers will be taking proceedings to secure his eligibility/participation in the Olympic and national trials in Birmingham from 11-13 July," said Nick Collins, the athlete's lawyer, in a statement.
There have been 26 successful appeals against the lifetime ban in the last 16 years - the last being 400m world champion Christine Ohuruogu's - but nobody has challenged the actual legality of the rule in the courts.
Until now, that is, and it appears the BOA could be facing two challenges, both involving clients of Leeds-based lawyer Collins.
Earlier this week Collins wrote to Britain's Olympic chiefs to tell them shot-putter Carl Myerscough, who failed a test for steroids in 1999, is considering legal proceedings.
We have got the sense from Dwain that he wants to help us ensure others don't fall into the same trap as him
The BOA remains confident its ruling will stand up in court but many legal experts worry it contravenes international regulations on the treatment of athletes returning from drugs suspensions.
Former World Anti-Doping Agency (Wada) president Dick Pound told BBC Sport in March he believed a legal challenge would be successful.
"As a matter of law, I think the BOA would be on pretty shaky ground," Pound said.
"If the BOA sought to deny me a place in the 2008 Olympic team on the basis solely of my earlier drugs offence, I would say they don't have the power to do that.
"I've always felt it was fairly clear what the outcome (of a challenge) would be."
Word of Chambers' decision to take the next step in his bid to make the Olympic team came on an eventful day for the 30-year-old as he spent the morning in talks with Britain's anti-doping authorities.
"It was a productive meeting, beneficial on all sides, and we hope it is going to create an ongoing dialogue" Collins told reporters afterwards.
UK Sport, the body which runs Britain's testing program, said it was pleased with Chambers' decision to come forward and reveal the details of his cheating.
Chambers should easily achieve the 10.85 standard to reach the trials
"We welcome the fact that Dwain has come in to speak with us," UK Sport's anti-doping chief John Scott said.
"We had a constructive and positive meeting and see it very much as the starting point of what we hope will be an ongoing relationship."
What is known of the meeting is that Chambers handed Scott a letter written by his supplier Victor Conte, as revealed by BBC Sport on Thursday, that detailed the full extent of his drugs use at the time of his positive test in 2003.
Conte was the founder and owner of the Bay Area Laboratory Co-Operative (Balco) which supplied Chambers with a range of performance-enhancing substances, including the tetrahydrogestrinone (THG) he was eventually caught using.
The letter given to UK Sport on Friday, however, revealed THG was one of seven banned substances Chambers was using.
Conte later served four months in prison for his central role in the Balco scandal that continues to damage elite sport's credibility, however he now seems determined to reinvent himself as an advocate for clean sport.
Conte remains close to Chambers and has been giving him nutritional advice. He has also told UK Sport he is willing to come to Britain to give its testers further intelligence that may help their anti-doping activities.
Scott, who prior to meeting Chambers had told BBC Sport he wanted complete honesty from him, admitted he was pleasantly surprised at the amount of information in Conte's statement.
"(Dwain) has provided a detailed account of his doping program which highlights the level of sophistication that goes into these systematic regimes," he said.
"It is through this sort of information that we are able to better understand both the mindset of why athletes choose that path and the network that sits behind them.
"It is these networks of manufacture, trafficking and supply that we need to be able to tap into if we are to get to the heart of doping in sport.
"Any athlete like Dwain who has taken drugs and is prepared to engage with us can potentially bring information which will help us develop the effectiveness of our anti-doping programme.
"We have got the sense from Dwain that he wants to help us ensure others don't fall into the same trap as him. We appreciate his openness and honesty and look forward to further dialogue in the future."
Whether Chambers has anything else of substance to offer Scott remains to be seen but it is clear his next challenge lies on the track. He must achieve the qualifying standard of 10.85 seconds to book his place in the national championships, which double as the Olympic trials.
Having secured a 60m silver medal at the World Indoor Championships in March, Chambers should comfortably achieve that standard the next time he runs for his club, Belgrave Harriers.
But even victory at the trials in Birmingham will be irrelevant unless he can overturn the BOA ban, and that will need recourse to the courts - an option fraught with danger for both him and the BOA.