NFL Backs New Jersey in Supreme Court Fight Over Kalshi and Sports Prediction Markets

The National Football League has sided largely with New Jersey officials who want the Supreme Court to take up a case on sports bets through prediction market platforms. In an amicus brief filed Wednesday, the league urged the justices to grant review of the petition from Attorney General Jennifer Davenport and gaming enforcement interim director Mary Jo Flaherty. The case could settle whether prediction market companies fall under state or federal authority. The league backed arguments about labeling sporting-event contracts as “swaps” and said review is needed to preserve game integrity and protect customers.

Game Integrity and Manipulation Concerns

The NFL said many event contracts are highly susceptible to manipulation. On the first Sunday of the football season, about $1.8 billion of the $3.3 billion traded across prediction markets, more than half, related to the NFL. The brief warned that a single person could influence outcomes, such as a player altering performance, a coach changing a lineup or an official making or skipping calls. It also criticized the lack of sensible safeguards from the CFTC and called federalizing sports betting a major question for the Court.

States Push for Clarity and Kalshi’s Response

On Wednesday, 39 states and the District of Columbia filed their own brief backing New Jersey, describing a national turf war between the CFTC and state regulators that only the Supreme Court can resolve. The Court has not said whether it will take the case. Kalshi has until Nov. 9 to respond on jurisdiction, manipulable contracts and consumer protection. A company spokesperson has said Kalshi cannot be regulated by 50 different regulators.