Dwain Chambers could take his battle to compete at the 2008 Olympics in Beijing to the High Court, his lawyer Nick Collins told BBC Radio 5 Live.
Chambers has been widely condemned on his athletics return
Under British Olympic Association (BOA) rules, the sprinter is banned from the Games after he tested positive for performance-enhancing drugs in 2003.
Chambers missed the BOA's deadline to appeal his exclusion from this summer's Olympics but could still challenge it.
Collins said: "An appeal may be to the BOA or straight to the High Court."
No British athlete has gone to the High Court before to take on the BOA over lifetime bans and Chambers would be the first to do so.
According to the governing body's rules, Dwain is entitled to compete - end of story
But Collins confirmed that Chambers is still unsure whether to appeal against his suspension and is concentrating solely on competing for Great Britain at next month's World Indoor Championships.
"There was a deadline set by the BOA to appeal against their ban which ran out on Friday (15 February), but we were only given very short notice of that," said Collins.
"I was with Dwain and we had a long and productive meeting and he is in very good spirits and is not going to rush into any decision regarding his appeal.
"Dwain is focused on his training and on competing in Valencia and he wants to do well for his country."
A spokeswoman for the BOA told BBC Sport the organisation has not received any correspondence from Chambers.
However, she stressed Chambers is still free to appeal against his permanent ban should he wish to attempt to challenge the BOA's ruling, which excludes any athletes who have failed drugs tests from competing in the Olympics.
"If athletes wanted to be certain that their appeal has gone through the whole system, then they needed to launch an appeal by the deadline," she told BBC Sport.
"However, it's not necessarily the only opportunity - Chambers can appeal at any given time."
The 29-year-old has been controversially included in Britain's squad to run in the 60m at the World Indoors in Valencia next month, despite UK Athletics' reluctance to select him.
Chambers was banned for two years after he tested positive for tetrahydrogestrinone (THG).
He made his comeback in 2006 and helped Britain's 4x100m team to European gold.
After a brief career in American Football in Europe, Chambers returned to athletics for a second time and won the 60m sprint at the world indoor trials on 10 February, a victory which earned him an automatic slot in the British team.
Chambers has already been hit by various snubs from future domestic and world athletics meets, as well as condemnation from administrators and former athletes.
Former Olympian and 100m runner Allan Wells threatened to sever ties with the BOA if Chambers was given the green light to compete in Beijing.