With sports wagering set to launch May 1, Colorado regulators on Thursday decided the state will have the ultimate say on what gamblers can — and cannot — bet on within sporting events.

The Colorado Limited Gaming Control Commission adopted rules governing the state’s new sports betting industry, including guidance on how so-called proposition betting opportunities will be determined.

Proposition, or prop, bets are wagers placed on individual players or events within a game, rather than the final score. During the Super Bowl, for example, gamblers could bet on which team wins the coin toss, who scores first or which quarterback throws the first touchdown pass — among dozens of other things.

According to the new rules, Colorado’s Limited Gaming Control Commission is in charge of approving not only which leagues are eligible for sports wagering, but also which “events” within those leagues’ games can be the subject of prop bets.

The Department of Revenue’s Gaming Enforcement Division will create a “catalog” or initial list of eligible bets to be continually updated and distributed to sports book operators in the state, director Dan Hartman said. If licensed casino or sports book operators want to add a prop bet, they can apply to offer it. Applications must be submitted at least 72 hours before the bet is open to public wagering.

“Once that bet is approved … it would be updated on that list and any operator would be able to take that bet,” Hartman said. “That catalog would be a living document.”

Proposition DD, which voters narrowly passed last November, legalized betting on professional sports, including individual, team, international and Olympic competitions, as well as collegiate, motor and sanctioned video-game sports. The commission expects to lay out exactly which sports leagues are permissible before the first bets can be placed May 1.

If a sports league or a specific event is not listed in the Gaming Enforcement Division’s catalog, operators may apply to have it added, just like a prop bet. The catalog also would enable operators and regulators to remove leagues or bets they no longer want to offer.

Not everyone agreed with this approach. At Thursday’s meeting, Mark Grueskin, an attorney representing several casinos including Ameristar, argued that such a catalog would be “unmanageable” considering the thousands of potential betting opportunities.

“This could be an extraordinarily long, changing day-by-day kind of list,” Grueskin said. “I know that the approved list is going to be a challenge.”

The commission debated creating a list of prohibited bets instead, but ultimately settled on the original approach. (Prop bets are not allowed on college sports, according to the state statute, nor is any wagering on high school sports.)

The regulations established Thursday, covering everything from revenue reporting protocols to how to maintain integrity in wagering, build on the licensing requirements previously put in place.

During the meeting, the commission also approved the first master licenses, enabling seven casinos in Cripple Creek, Black Hawk and Central City to move forward with sports betting once it’s legal May 1. Under the new law, sports betting can take place at licensed casinos in those three mountain towns or through internet sites or mobile apps affiliated with licensed Colorado casinos.