WASHINGTON — The U.S. Senate passed a resolution banning senators and their staff from trading on prediction markets, effective immediately, amid concerns over potential conflicts of interest and insider information.
Senators approved the measure by unanimous consent on April 30, amending the chamber's standing rules to prohibit participation in event contracts on platforms such as Kalshi and Polymarket. The resolution, sponsored by Sen. Bernie Moreno, Republican of Ohio, extended the ban to Senate officers and employees following an amendment.
The move addressed growing scrutiny of prediction markets, where participants bet on outcomes of political events, elections and policy decisions. Critics had raised questions about the use of nonpublic information by lawmakers.
" No Member of Congress should be able to profit off their insider knowledge by placing informed bets on prediction market platforms," said one supporter of similar restrictions, according to reports.
The Senate action followed reports of substantial trading volumes on platforms dealing in contracts tied to U.S. government actions and elections. Major platforms had already implemented some restrictions on congressional participation, but the new rule formalizes the prohibition for the upper chamber.
The resolution calls on the House of Representatives, the executive branch and the judiciary to consider similar measures. As of June 2026, the House has not adopted a comparable chamber-wide ban, though individual members and bipartisan proposals have advanced related legislation.
Prediction markets allow users to buy and sell contracts based on the probability of specific events occurring. Proponents argue they provide insights into collective expectations, while opponents cite risks of manipulation and ethical concerns for public officials.
Details remain unclear on the full enforcement mechanisms or any potential penalties for violations under the Senate rule. The ban applies to contracts dependent on the occurrence or nonoccurrence of specific events or contingencies, as defined under commodity trading regulations.
The development comes as broader legislative efforts to regulate prediction markets and restrict congressional trading in stocks continue in Congress. Some lawmakers have introduced bills to extend prohibitions to family members and former officials.
Senate leaders from both parties supported the resolution. As of Monday, no immediate challenges to the rule have been reported, and discussions about House action remain ongoing.
The Senate's decision marks one of the quicker self-imposed restrictions in recent congressional ethics debates.
