“However, the absence of this evidence means that the question of whether others had knowledge of, or were implicated in, the systemic Aquanita doping can never be answered.”

Carroll said he had also explored whether there were any conflicts of interest, given the personal relationships of Racing Victoria staff with Aquanita board and committee members.

But he found no evidence of improper action.

“Many of the complaints received by my office relate to the potential conflict of interest of board and committee members and staff of both RVL and the MRC, and the impact this had on the investigation and subsequent decision-making about disqualification of Aquanita-trained horses and re-distribution of prizemoney,” Carroll wrote.

“I have found no evidence of any undeclared conflicts of interest, improper or inadequate management of any declared conflicts, or inappropriate participation or interference in any Aquanita decision-making by any person, including in relation to decisions to disqualify horses.

“I am also satisfied that no person with an Aquanita conflict of interest was involved in the decision not to recoup prizemoney that had already been paid to horses that were subsequently disqualified. I otherwise consider that this decision was a commercial one that was open to RVL to make. Any recovery of fines imposed by the Victorian Civil and Administrative Tribunal is also at the discretion of RVL.”

Carroll has previously identified shortcomings in Racing Victoria investigations and recommended changes to processes, most notably following the bungled Richard Laming case, when a steward acted improperly during a Victorian Racing Tribunal case, causing stomach tubing charges to be withdrawn.

Carroll said because those previously made recommendations had been adopted by Racing Victoria, he did not see the need to make further recommendations to improve the system used by stewards to investigate doping claims.

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