It is alleged he punched another trainer leaving him with a black eye after a verbal altercation centred around the ongoing police investigation into corruption in the harness racing industry, codenamed Operation Inca.
The trainer has pleaded not guilty and has interim name suppression.
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Operation Inca is an investigation into alleged race-fixing and drug-related matters.
A number of people in the industry are before the courts on various charges.
The assault charge comes as another Canterbury racing trainer Nigel McGrath pleaded guilty to three racing charges brought by the Racing Integrity Unit earlier this month after a raid at his Weedons property.
McGrath pleaded guilty to attempting to administer a prohibited substance on a race day, refusing to supply information to a racecourse inspector and obstructing a racecourse inspector during an investigation.
He has denied an allegation of tubing a horse with banned substance sodium bicarbonate.
Racing’s Judicial Control Authority, which heard the case, has yet to impose its penalty on McGrath, who could face a lengthy ban.