Maher claimed he did not know about Foster's involvement in the horses but admitted he should have asked more questions about the bona fides of them, especially group 1 winner Azkadellia.

Racing Victoria chief steward Terry Bailey said after the hearing that the case had been an exhausting 12 months that had called on many of the resources of the integrity department as it had assigned four investigators in the past year to concentrate on the case.

Azkadellia, Little Bubulu, Lovable Rogue, Hart and Mr Simples are still unable to race.

Maher pleaded guilty to a charge of conduct prejudicial to the image, interests or welfare of racing.

RAD chairman, Judge John Bowman, told Maher that the panel found his offending did not warrant a disqualification but was of such gravity that only a term of suspension could be considered.

In a letter to owners sent out shortly after the hearing on Monday, Maher said: "As you have probably just heard, I have pleaded guilty to section 175A and today the RAD board has suspended me for six months and fined me $75,000. The suspension begins on October 2.

"While I am disappointed to find myself in this situation, I am relieved a decision has been finally made. I would like to thank the RAD board for their consideration of my case.

"The past 12 months have certainly taken a toll on my health, however, I have an incredibly supportive team at Ciaron Maher Racing who will be able to ensure the smooth running of the operation in the interim."

Maher will have to vacate his Caulfield stable by next Monday, when the six-month suspension period begins.

Maher has more than 100 horses in his stable and will now need to find a replacement to fill the role as head trainer until early April next year.

Maher will not be able to visit his stables nor attend track work during the week to observe the horses he once trained.

Stewards' barrister Dr Cliff Pannam, QC, said Maher did not know about Foster's involvement but should have asked questions.

Azkadellia was owned by Foster but was listed as being owned by Maher's racing manager, Ben Connolly, along with Little Bubulu, Loveable Rogue, Hart and Mr Simples.

Connolly confessed that Foster was involved in the ownership of the horses, the Racing Appeals and Disciplinary board heard on Monday.

"Mr Maher's failure to act facilitated the ongoing involvement of a notorious convicted criminal in the ownership of the horses," Pannam said.

The board rejected a defence submission that any suspension be itself suspended.

Bowman said Maher ought to have known there were questions about the horses' ownership, particularly Azkadellia, and that it probably involved notorious convicted conman Foster.

"Your serious lapse of judgment could be seen in enabling the perpetration of the fraud," Bowman said.

The board heard Maher contacted stewards after a November 2014 article suggested Foster may be involved with the horses.

Pannam said Maher did not ask whether Foster, his niece Arabella, whose company was listed as the owner, or any of the conman's associates were involved in the sale to Connolly.

Nor did he ask how Connolly, a racing manager on an $80,000 salary, could afford to buy the five horses and pay the training fees.

"It screamed out, in the stewards' submission, for inquiry," Pannam said.

"No inquiry was made."

The tribunal heard Azkadellia was a $260,000 filly when purchased but Connolly paid $60,000, which Maher considered to be cheap.

Pannam said Connolly owed Maher $75,000 in training fees in May 2016 but the trainer made no attempt to press for payment despite knowing Azkadellia had already won a substantial amount of money.

Pannam said Maher had dinner with Foster, Foster's niece and others the same month, but still made no inquiries.

The barrister said Connolly eventually told stewards about Foster's involvement and then owned up to Maher in September 2016, but the trainer initially denied having been told.

Maher has apologised to stewards, saying he accepted he did not measure up to the responsibilities that come with being a trainer.

Peter Morrissey, SC, acting for the trainer, said that his client "ardently wishes to remain in the industry".

Just last year Maher had one of his finest moments in racing when his high-class mare Jameka raced away with the Caulfield Cup. However, her career has been curtailed due to illness.

with AAP