U.S. lawmaker proposes ban on House members using prediction markets

U.S. Representative Bryan Steil (R-Wis.), chairman of the House Administration Committee, has introduced legislation that would bar House members, their spouses and dependent children from participating in prediction markets, amid growing scrutiny of lawmakers’ financial activities.

The proposed Stop Lawmakers From Predicting Act is part of broader efforts in Congress to prevent lawmakers from using their positions for personal financial gain.

The measure targets participation in prediction market platforms such as Kalshi and Polymarket, which allow users to trade contracts tied to the outcomes of political, economic, and other events.

The nascent industry has seen an explosion of growth amid a friendlier regulatory environment under President Donald Trump, but that attention has also brought new scrutiny, including from Congress.

“The American people deserve to know their Member of Congress is not profiting off insider information,” Steil said in a statement. “Lawmakers should be writing policy, not wagering on its outcome.”

Under the bill, members found in violation would be required to pay a fine equal to the greater of $2,000 or 10% of the value of the transaction, in addition to any net gains derived from it. The legislation would also prohibit lawmakers from using official office funds or campaign funds to pay penalties.

The proposal does not extend to congressional staff, but some lawmakers have already banned their staff from wagering on prediction markets. 

The legislation follows action in the Senate, which unanimously approved a measure in April banning senators and staff from participating in prediction markets. U.S. Representative Ashley Hinson (R-Iowa) introduced legislation shortly after to amend House rules and impose a similar prohibition, urging House leadership to bring the measure to the floor “immediately.”

However, House Republicans did not immediately move forward with a House ban on lawmakers participating in prediction markets. Speaker Mike Johnson (R-La.) has said he wants to ensure there is consensus before moving forward, while House Majority Leader Steve Scalise (R-La.) has pointed to Steil’s legislative effort and said committees exist to “get this right.”

Lawmakers’ concerns about insider trading on prediction markets reached a new high earlier this year after federal authorities charged a U.S. soldier with allegedly using confidential information to trade on the capture of then-Venezuelan leader Nicolás Maduro on Polymarket.

Trading activity linked to former Republican congressman George Santos has also been referred to federal authorities. The case centers on bets placed on prediction market platform Kalshi regarding whether Santos would attend President Donald Trump’s State of the Union address.

According to reports from NPR and CNN, Kalshi identified suspicious activity in the market, determined that the account belonged to Santos, froze the account, and referred the matter to both the U.S. Department of Justice and the Commodity Futures Trading Commission.