An inquiry commission set up by cycling's global governing body the UCI appealed to riders who were doped in the past to come forward in exchange for reduced punishment.
"The primary purpose of our investigation is not to punish doping offenders but to learn from the past so we can help ensure a better future for cycling," commission chief Dick Marty said in a statement.
"We will treat all witnesses fairly and so I urge anyone in the cycling community with information that can help our investigation to come forward," he added.
The three-member Cycling Independent Reform Commission was set up in January to investigate historic doping in cycling and allegations that the UCI had been involved in previous wrongdoing.
The commission said its main goal is to determine how a culture of doping was perpetuated between 1998 and 2013, and to establish who was to blame.
It has the power to propose reduced sanctions to any rider, official, agent, race organiser or team staff member who admits to an anti-doping offence.
It can reduce the sanction further if the individual provides valuable information concerning doping practices, and is also empowered to let those who confess keep past prize money.
And it also has the power to propose case-by-case reductions for anyone currently suspended from the sport and who reveals more details -- though any such softening will have to be approved by the original sanctioning body, the UCI and the World Anti-Doping Agency.
Its probe is to conducted on a strictly confidential basis, it underlined.
