Senate bans members, staff from prediction market trading

The Senate unanimously approved a change to chamber rules on Thursday that bans senators and Senate staff from trading on prediction markets that trade on political and world events.

The resolution will be enforced internally by the Senate and does not create a federal crime or require approval by the House or the president. Violations will be policed by members of the chamber under the new rule.

Senator Bernie Moreno wrote on X that “Serving in Congress is an honor, not a side business,” adding that “Americans deserve to know that their leaders are here for the right reason.”

Lawmakers acted after several instances in which anonymous bettors made profitable trades shortly before major announcements and after federal prosecutors charged a member of the U.S. military in an insider-trading case. Prosecutors last week charged U.S. Army Special Forces Master Sergeant Gannon Ken Van Dyke with insider trading tied to the removal of Venezuelan President Nicolás Maduro. Authorities allege Van Dyke used nonpublic operational knowledge to place bets on Polymarket. A civil complaint from the Commodity Futures Trading Commission says he made more than $404,000 in illicit gains.

Members of Congress have introduced bills that would place broader limits on prediction-market trading. Representative Ritchie Torres filed the Public Integrity in Financial Prediction Markets Act of 2026 to bar federal officials from trading on these platforms. Senators Jeff Merkley and Amy Klobuchar proposed legislation to prohibit senior executive-branch officials from such trades. A bipartisan House proposal from Representatives Blake Moore and Salud Carbajal targets insider trading tied to sensitive military information and democratic processes. Other measures seek to ban markets tied to sports betting or outcomes such as terrorism, assassination, war or the death of an individual.

States and employers have issued similar restrictions. Illinois Governor J.B. Pritzker ordered state employees not to use insider information for prediction-market wagers, and several organizations have put limits on staff participation in these markets.

Polymarket deputy chief legal officer Olivia Chalos wrote on X that the platform “operates in full compliance with applicable law, and our insider trading rules are the exact lines that the CFTC and courts draw for derivatives markets,” and said the company shares a commitment to national security and market integrity. Senator Richard Blumenthal criticized Polymarket for permitting markets tied to national security events and cited a market that allowed bets on the rescue of a U.S. service member in Iran.

The Senate change creates an internal restriction on members and staff while Congress considers whether to enact broader federal rules that would create enforceable prohibitions beyond the chamber’s authority.