Over 100 horses are set to be disqualified after the uncovering of a large-scale attempt to evade integrity rules.

The Horseracing Integrity and Safety Authority was established in 2020 to oversee and enforce a uniform set of rules across the US.

An investigation involving its team from the integrity and welfare unit and the Pennsylvania State Horse Racing Commission has found evidence of an alleged conspiracy involving a vet and 13 trainers at Penn National racecourse.

HISA claims the group flouted protocols by giving intra-articular injections to joints of horses before running during a period when it was forbidden, under integrity rules designed to safeguard equine health and ensure fair competition.

Three of the horses subsequently died while nearly a third of those involved never ran again.

In a statement HISA announced that cases were being pursued against veterinarian Dr Allen Post Bonnell who allegedly conspired with the trainers from May 2023 to November 2024.

“As a result of the alleged violations, HISA and HIWU will pursue sanctions against these Covered Persons as described in HISA’s rules, including the disqualification of more than 100 horses from previous race results and subsequent forfeiture of purses, periods of Ineligibility for the Covered Persons and fines,” HISA said.

“While all horses were allegedly injected at Penn National Race Course, they participated in races at 10 different racetracks subject to HISA’s rules, across six different states.

“HISA has verified that of the more than 100 unique horses alleged to have breezed or raced in violation of HISA’s intra-articular stand down times, 30% never raced again, strongly suggesting these injections were used to mask pain.

“Approximately 10% were observed to be lame post-race by a regulatory veterinarian. Three horses were euthanized as a direct result of injuries sustained in those races.”

HISA CEO Lisa Lazarus said: “This egregious breach of integrity and intentional undermining of equine welfare is a stark reminder of why rigorous oversight and enforcement are critical to the future of horse racing.

“The health and safety of horses and jockeys are paramount, and those who deliberately put them at risk will be held accountable.”

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