RACING Victoria stewards will seek leave to appeal to the Court of Appeal against the finding of the Supreme Court that overturned a three-year disqualification last month on trainer Mark Riley.

PATRICK BARTLEY reports for FAIRFAX MEDIA that the Racing Appeals and Disciplinary (RAD) Board and the Victorian Civil and Administrative Tribunal had disqualified Riley for the alleged administration of a prohibited substance to the horse Gold For Kev in July 2014.

RVL said last night as the matter remained before the courts stewards would be making no further comment at this time.

Meanwhile, Jeff Gleeson, SC, for Racing Victoria, grilled trainer Shannon Hope at length over cobalt positive charges on the fourth day of hearings into the matter.

Gleeson said that Shannon Hope was lying in his testimony that he didn't know how his three horses had returned such high levels of cobalt late last year.

Hope blamed the feeding regime that he and his father were using as the reason the levels were so high.

"My father brought me up to not tell lies and I'm not telling lies. I've seen horses treated by cobalt and it's not a good look," Hope said.

Gleeson said to Hope that everyone made mistakes and that he should admit to this one. Hope replied "I did not." Earlier in the day under cross-examination by Gleeson, Lee Hope – the Seymour trainer who along with his son is charged with cobalt offences – said "definitely no" to ever using cobalt. Hope said he had no knowledge of cobalt and was mystified when Racing Victoria compliance team member Dion Villella and former investigator Kane Ashby arrived at his Seymour property advising him of elevated readings in two of their horses.

Hope told the RAD Board that last October he had no knowledge of the use of cobalt and thought stewards had made a mistake.

The compliance team thoroughly searched the property stables and the garage while analysts tested packaged substances to ensure they matched their labelling. All were found to be in order.

Lee Hope, who has been involved in the racing industry for 50 years, explained that when his vet, Dr John Veenendaal, became seriously ill, they had to change to Sydney-based vet Dr Tim Roberts.

"He looked at what we were using [as supplements] and said, 'You've got cobalt there, cobalt there, cobalt there, you've got to change it'," Hope said.

RAD Board chairman, Judge Russell Lewis, said the board would hear more submissions on November 4.