Chambers (30) is currently subject to a lifetime ban from competing at the Games after being uncovered as a drugs cheat.

The punishment was automatically meted out by the British Olympic Association (BOA) after Chambers received a two-year suspension after testing positive for the designer performance-enhancing steroid THG in 2003.

But now the 100m runner has launched a high-profile legal challenge to the BOA ruling in the High Court.

He wants to run at this weekend's national championships in Birmingham, which double up as the Olympic trials, and then the Games in Beijing, China.

And 110m hurdler Turner, who is guaranteed a seat on the plane for Beijing as part of the Great Britain team, is backing Chambers' bid.

"I try not to get involved," said 27-year-old Turner. "But personally I think he has done his time so let him race. Just let him run."

Turner revealed that he regularly trains with Chambers and that the former European champion offered support as he recovered from a recent hamstring tear.

"I get on with him and he is a good guy," said father-of-two Turner. "When I returned after the injury for a training session I was really nervous and he was there to motivate me and give me help to get through it.

"Dwain is always saying that he did what he did dirty but now he is clean and he wants to prove himself."

Chambers was given leave to compete for Britain in March's Indoor World Championships by UK Athletics and raced to 60m gold.

He has already achieved the Olympic qualifying time in Germany and recorded a time of 10.05 seconds in Sofia this week – the fastest time by a Brit for six years.

Depite this, opinion is divided on whether he should be allowed to compete in Beijing.

The British Athletics Commission has launched a petition against Chambers' bid and signatories include five-time Olympic gold-medal rower Sir Steve Redgrave and double Olympic gold medallist Dame Kelly Holmes.

However Turner said: "It frustrates me that every time he (Chambers) overcomes one barrier another one is put up in front of him.

"He has been through a lot. Yes, he has cheated, but he has done his time.

"He has gone into the offices and told officials where he got the drugs from and how he did it. He is trying to help and make a difference. Just let him run and get on with his life.

"I hear rumours about Americans who have been caught taking drugs and it has been brushed under the table. I think there is a big cover up and it is just the unlucky ones who get caught.

"Officials are shooting themselves in the foot. If there was a rule that said if you get caught you are finished, full stop, then there wouldn't be a grey area. But they keep leaving doors open."

The hearing in the High Court is scheduled to last two days and is against a BOA bye-law that has been in existence for 16 years and imposes automatic life bans unless there are mitigating circumstances.

The rule is at odds with the position of track and field governing body the International Association of Athletics Federations (IAAF), who say athletes found guilty of doping can return to all competitions once they have served their bans.

There have been successful appeals against the lifetime ban – the last being 400m world champion Christine Ohuruogu's – but nobody has challenged the actual legality of the rule in the courts.