The lengthy suspension of controversial jockey Danny Nikolic has sent a powerful warning from the industry, according to Racing Victoria boss Rob Hines.

Hines has strongly backed the decision by the Racing Appeals and Disciplinary (RAD) Board to suspend Nikolic for two years after he was found guilty of abusing and threatening Victoria's chief steward Terry Bailey.

The incident would leave a stain on racing, Hines said, but tough action needed to be taken.

"I do think the RAD board has sent a pretty clear message with these periods of disqualification," Hines told RSN radio on Wednesday.

"I have to say they are in line with the periods the stewards requested."

Hines rejected a proposal put forward by Nikolic's defence that the board follow the procedure in the UK where a suspension of up to 41 days is usually imposed in such cases.

"Every case is different. I don't know if you can say they are similar offences," Hines said.

"This decision was heard based on all the evidence and all the opportunities that the defendant had to put forward his case.

"I think everyone's had a fair hearing. I think the system we have in racing is terrific with the independent RAD board.

"They are judges and barristers of the highest standing - they're completely independent of Racing Victoria.

"We've seen decisions go the other way against stewards that we perhaps wouldn't support."

Hines said that there would always be a small percentage of people in the racing industry who brought the sport into disrepute.

"I don't think we'll ever get away from the occasional issue that makes (news) for the wrong reasons and we have to live with that," he said.

"What we've got to do though is show everyone in this industry there are a very, very small percentage of people who are doing the wrong thing and if they breach the rules of racing we will pursue them."

He also supported evidence from Bailey who said he and his family had been threatened by Nikolic, even though there were no independent witnesses.

Hines said Bailey was "an outstanding individual and he's doing a fabulous job".

"Terry has been very courageous in his stand and we have to have the stewards and the integrity department act without fear or favour and I believe they've done that."

Nikolic is likely to appeal his ban, which bars him from riding, betting on races or stepping onto any racecourse in Australia, to the Victorian Civil and Administrative Tribunal.