It looks like a slot machine. Legally, it is a horse race.
01
A real past race is selected
The machine draws from a database of thousands of actual historical races. All identifying details — horse names, track, date — are stripped out before you see anything.
02
You see anonymized statistics
A brief window of data appears: speed figures, past performance numbers. No names. No context. You have no way of knowing which race this is, or who won it.
03
You pick a horse and place your bet
Your wager goes into a pool with all other bets placed on that race across every machine. The more people who bet on your horse, the smaller your potential payout.
04
The race plays out. The pool pays out.
The historical race runs on screen. Winning tickets split the pool after the track's commission is deducted. The experience is indistinguishable from a slot machine.
Because bettors are wagering on real horse races using the pari-mutuel pool system, HRMs are classified as horse racing wagering — not casino gaming. This classification lets them operate at racetracks under state racing commission oversight, bypassing the casino licensing process. Kentucky codified this in Senate Bill 120 (2021), which formally defined Historical Horse Racing as pari-mutuel wagering and required that a portion of tax revenue flow into thoroughbred purse accounts.
Source: Kentucky Senate Bill 120 (2021); Kentucky Horse Racing and Gaming Corporation; CDI quarterly earnings releases