Baffert was banned from entering horses at CDI-owned tracks through this year's spring races after five drug-related violations in a 12-month span, including the positive test for a banned drug by 2021 Kentucky Derby winner Medina Spirit, who died later that year.
The following February Medina Spirit was disqualified as the 2021 Derby winner after a banned steroid was revealed in tests.
Baffert's suspension was extended, a statement from Churchill Downs Incorporated (CDI) said, over concerns about the potential safety threat posed by Baffert, who has trained horses that have won 17 US Triple Crown races, including six Kentucky Derby titles.
"Mr. Baffert continues to peddle a false narrative concerning the failed drug test of Medina Spirit at the 147th Kentucky Derby, from which his horse was disqualified by the Kentucky Horse Racing Commission in accordance with Kentucky law and regulations," the statement said.
"Prior to that race, Mr. Baffert signed an agreement with Churchill Downs which stated that he was responsible for understanding the rules of racing in Kentucky and that he would abide by them.
"The results of the tests clearly show that he did not comply and his ongoing conduct reveals his continued disregard for the rules and regulations that ensure horse and jockey safety, as well as the integrity and fairness of the races conducted at our facilities," CDI added.
"A trainer who is unwilling to accept responsibility for multiple drug test failures in our highest-profile races cannot be trusted to avoid future misconduct."
Baffert will remain suspended from entering horses at all CDI-owned racetracks through 2024. "After such time, we will re-evaluate his status," CDI said.
The extended suspension comes after 12 horses died at Churchill Downs within a month around derby time, prompting the track to launch an investigation into safety issues.
Baffert was suspended from other Triple Crown races last year by authorities in Maryland and New York but was back at this year's Preakness and Belmont Stakes.
Baffert-trained National Treasure won May's Preakness at Baltimore.
