Ms Turnbull, the daughter of Bathurst harness racing legend Steve Turnbull, was one of four people arrested by Victorian police for questioning on Sunday night.

All were released without charge.

Ms Turnbull, the lead female harness driver in NSW at the moment, is now based at Menangle, but was previously based at The Lagoon.

In a statement, Harness Racing Victoria (HRV) said its Integrity Department initiated an investigation in June 2015 into matters relating to the conduct of a race at Cobram on June 22, 2015, particularly with respect to the training arrangements and betting activity.

The extensive investigation conducted by the HRV Integrity Department resulted in it referring the matter to the Victoria Police Sporting Integrity Intelligence Unit (SIIU) in November, 2015, for further investigation.

On Sunday night, detectives from the SIIU arrested Ms Turnbull, her boyfriend Nathan Jack, and two other people for questioning.

No charges were laid and all four were later released pending further inquiries.

Mr Turnbull said his daughter was an “innocent victim”.

“We are all devastated,” he said on Monday.

“She is an innocent victim in the whole show.

“She is so upset. She didn’t even go to the meeting [where the alleged race fixing occurred] and wasn’t down as the trainer.

“She is really stressed to think these allegations have come against her name. All they are at the moment are rumours.

“She was questioned on Sunday night and released without charge. Anything else [being said] is just rumour.

“It’s a bad time for all of us. She is very shaken over the whole incident.”