A group that represents horse breeders, trainers, owners and drivers filed a lawsuit Monday challenging the constitutionality of a new state law that could end decades of harness racing in Florida.

The Florida Standardbred Breeders & Owners Association filed the lawsuit in Leon County circuit court, after lawmakers in May lifted a longstanding requirement that Pompano Park – the only harness track in the state – run live races to continue offering other types of gambling.

The lawsuit contends, in part, that the law violates constitutional equal-protection rights because it treats harness racing different than thoroughbred racing. The Legislature did not lift a requirement for live racing at thoroughbred tracks.