The RSPCA concedes it botched an investigation into an illegal knackery where more than 500 dead horses were found near Wagga Wagga.
The animal welfare group found just 20 carcasses across multiple visits to the site and initially identified no breaches, but officials later admitted they had not looked inside a coolroom said to have contained a large amount of horse meat.
An NSW parliamentary inquiry is looking into the aerial shooting of brumbies in Kosciuszko National Park, however questioning on Thursday largely focused on the knackery allegations.
The state government suspended its brumby rehoming program following allegations more than 250 of the wild horses were sent to a person linked to the informal slaughterhouse.
Racing NSW told the RSPCA about dead horses on the property at Wagga Wagga, in the NSW Riverina region, in September 2023.
But the knackery was not uncovered during visits either that month or in January 2024.
Wagga Wagga City Council subsequently investigated the matter and announced in April that more than 500 horses appeared to have been slaughtered at the 20-acre property.
RSPCA chief executive Steven Coleman conceded the animal welfare body should have referred the matter to other agencies and checked the coolroom while officials were at the site.
"Our inspectors, like police, have to make judgement calls every day, every complaint that they attend," he told the inquiry.
"You would think it would be hard to miss 500 carcasses - you're right."
His comments prompted a scathing response from Nationals MP Wes Fang, who questioned how the RSPCA's advice on the controversial aerial culling program could be trusted when it mishandled the knackery probe.
"How can anybody in NSW, given the number of failures that your organisation has overseen, have any confidence in the advice, in the enforcement, in the investigations that your organisation does," he said.
The NSW Department of Primary Industries previously said officials seized 300kg of meat from the property.
Rehoming of wild horses is part of the state government's management plan for Kosciuszko National Park, where there is a legislated target to cut the brumby population to 3000 by 2027.
Recent counts showed there were up to 22,500 horses in the park, officials have said, prompting a return under the state Labor government of aerial shooting to bring down numbers.
The feral horse numbers have exploded since then-NSW Nationals leader and deputy premier John Barilaro opposed culls in favour of trapping and rehoming in 2018.
