The Australian Sports Anti-Doping Authority has completed its investigation of the AFL and NRL, the body's chief told a Senate hearing on Wednesday.
Outgoing ASADA chief executive Aurora Andruska said the authority was now reviewing the evidence it had gathered and developing briefs.
Andruska said former Federal Court judge Garry Downes would review the evidence to determine whether it was sufficient to take cases forward.
But she said Downes' work would not hold up the authority's work, and it would continue to prepare briefs and could issue show cause letters to players and take matters through the Anti-Doping Rule Violation panel and other tribunals while Downes completed his review.
ASADA said an Australian Federal Police and Deloitte investigation had found no one within their organisation was responsible for leaking sensitive information to the media.
During the peak of ASADA's investigation into players in the NRL and AFL, several sensitive documents were published in the media last year that related to football clubs Cronulla and Essendon.
It was enough to force Andruska to call in the AFP and Deloitte to go over the organisation with a fine-tooth comb.
"There were media suggestions, and from other quarters, that the organisation was leaking," she told a Senate estimates hearing on Wednesday.
"I brought in Deloitte and the AFP to make examination of any leaks occurring, and there were none. ASADA was not leaking."
Andruska said the investigation examined all communication that had been made and received by the organisation over the past several years.
She said she could only speculate where the leaks came from, and when invited by the senators to do so, replied: "I don't think that's an answer I'd give".
The investigation into both Cronulla and Essendon's supplements programs has been completed, but ASADA is reviewing its evidence meaning players could still be issued with infraction notices.