Leading trainer Robbie Griffiths says he is shocked Racing Victoria stewards were considering using a spy in covert operations in racing stables.

The claims surfaced after fellow trainer Peter Moody had a Pakenham runner scratched on Wednesday over suspected raceday treatment.

In his role as president of the Victorian arm of the Australian Trainers' Association, Griffiths said the the use of spies in stables would be a hot topic at the branch's next meeting.

"That shocked me," Griffiths said.

"We offer up our keys and access to our facilities and let them take as much blood and urine tests of horses.

"As Peter said yesterday, and what we all want, is a clean, level playing field, so I can understand why he feels victimised after hearing that.

"That didn't sit well with me."

Moody has indicated he could easily step away from racing after this latest episode which comes on top of an impending hearing on cobalt charges.

Griffiths said it would be sad to lose a trainer of Moody's standing from racing.

"When I get asked questions, there's two of me," Griffiths said.

"There's the fellow trainer that holds a licence and can be in all the situations as easily as Peter, and then there's me in a trainers' leadership role.

"Robbie Griffiths, trainer, mates with Peter Moody, it would be very sad to see him throw the towel in under these circumstances."

Griffiths said the Victorian branch of the ATA had fought hard to get some concessions on a new rule.

The rule, which comes into effect on October 1, means a horse cannot have an intravenous drip or have blood taken from it one clear day before a race.

In Victoria, trainers can make an application to take blood from a horse for testing.

Griffiths said he hoped the increased integrity helped punters feel comfortable that racing is the leading model in sports betting.