Big punter Eddie Hayson could find himself unable to have a bet after being asked to show cause why he should not be warned off racetracks.

Racing NSW is set to meet next month over Hayson's refusal to provide the names of people who gave him information about the top racemare More Joyous before she ran in the All Aged Stakes.

The consequences of being warned off include not being permitted to enter any racecourse or training facility, not being able to have an interest in any thoroughbred racehorse and not being able to place a bet with a wagering operator.

Hayson was a witness at the high-profile inquiry into More Joyous' performance in the Group One race on April 27 in which she finished second last, sparking a public tirade by her owner John Singleton against trainer Gai Waterhouse who he sacked in post-race television interviews.

Singleton also accused the trainer's son, bookmaker Tom Waterhouse, of telling the Nine Network's Andrew Johns the mare could not win.

Tom Waterhouse was cleared of any wrongdoing and Hayson gave evidence he had decided not to back the mare based on information given to him by two people, one of whom he said had a connection to the Waterhouse stable.

He has refused repeated requests from Racing NSW to provide the names, prompting the governing body to issue a notice on Friday to show cause why he should not be warned off.

A Racing NSW committee has been set up to hold the show cause hearing on August 13 and make a recommendation to chief executive Peter V'landys whether Hayson should be warned off.