A professional harness racing driver denies he put the industry at risk by bringing uncleaned horse gear back to Christchurch International Airport after a meeting in Sydney.

The Ministry of Primary Industries pointed out the risk from the deadly hendra virus when 46-year-old Anthony Murray Butt pleaded guilty to a breach of the Biosecurity Act today.

Butt was not convicted at the request of defence counsel Elizabeth Bulger who may seek a discharge without conviction at his sentencing on March 14.

Prosecutor Grant Fletcher said hendra virus posed a significant biosecurity risk to New Zealand's racing industry which employed 18,000 people.

Introduction of the virus would cause significant economic damage.

He detailed outbreaks of the disease in Australia which had caused the deaths of horses and trainers.

He said Butt had arrived at Christchurch airport on a flight from Sydney on August 28, and had not declared that he had been in contact with animals.

He was a regular traveller overseas to race horses but did not declare on that day that he had horse racing gear which had not been cleaned.

The gear he had, including boots, clothes, and goggles, was very soiled, Fletcher said.

Investigators confirmed on video coverage that the clothing had been used at a race meeting in Sydney that day.

Butt told officials that "being in a race wasn't being in contact with horses", and that the gear had not been used in Australia for racing.

Bulger said she was at odds with the prosecutor over the risk posed by hendra virus, and the penalty that should be imposed. 

She said Butt "takes some considerable issue with the indication that he was putting the racing industry in any sort of danger".

- © Fairfax NZ News