Tim Brennan faces a British Horseracing Authority disciplinary panel hearing over whether he committed a corrupt or fraudulent practice in his role as a vet by passing on inside information regarding the 2016 Champion Hurdle prospects of Faugheen.
At the time, Faugheen was the reigning champion and Brennan was used by Willie Mullins, who is not involved in any wrongdoing.
Faugheen won the Irish Champion Hurdle at Leopardstown in January 2016, but Mullins ruled him out of the Champion Hurdle on February 17 of that year with a "sore suspensory ligament" injury.
Between January 24, 2016 and February 20, Brennan is accused of passing inside information to his brother, Michael, which was subsequently used to gain an unfair advantage in the betting market. Michael Brennan has already been excluded from the sport.
A statement issued by the British Horseracing Authority said the hearing, which is due to take place on July 16 and 17, will assess whether or not Brennan passed on information "which might be used to gain an unfair advantage in the betting market intending to make a gain for himself or another and/or to cause loss to another".
A BHA disciplinary panel will also consider whether or not Brennan "enabled and/or assisted Michael Brennan to cheat at gambling in relation to the 2016 Cheltenham Champion Hurdle".
If found guilty of an offence, Tim Brennan could be disqualified from the sport for between six months to 10 years.
Brant Dunshea, chief regulatory officer for the BHA, said: "We cannot comment further on the specifics of the charges against Timothy Brennan as this matter is still to be heard by the independent disciplinary panel.
"However, we can confirm that Michael Brennan, who was a person of interest in this investigation, has been excluded from the sport as a result of his failure to cooperate with the investigation.
"This failure to comply has resulted in the investigation process taking longer than it otherwise would have done. However, it has ultimately not prevented us from bringing charges and has also seen the individual ejected from the sport in Britain.
"Since the introduction of a fast-track investigation process for minor offences - which was a recommendation of the integrity review - we are significantly reducing the time taken for most cases to be dealt with."