Senate bans lawmakers, staff from trading on prediction markets

On Thursday the Senate voted unanimously to change the chamber’s internal rules, barring senators and their aides from trading on commercial prediction markets tied to political, national security or other government-related events.

The resolution will be enforced internally by senators. It does not create a criminal prohibition, does not require approval by the House and does not need the president’s signature. Violations will be handled under the Senate’s existing disciplinary procedures.

Republican Senator Bernie Moreno of Ohio sponsored the change. In an online post he wrote, “serving in Congress is an honor, not a side hustle,” and added that Americans deserve to know their leaders are acting for the right reasons.

Lawmakers cited concerns about insider trading and conflicts of interest after recent law enforcement actions. Last week federal prosecutors charged U.S. Army Special Forces Master Sergeant Gannon Ken Van Dyke, alleging he used nonpublic knowledge of the ouster of Venezuelan President Nicolás Maduro to trade on a prediction platform.

A separate civil complaint filed by the Commodity Futures Trading Commission alleges Van Dyke made more than $404,000 in illicit profits. Prosecutors say he took part in planning and executing the operation referred to as Operation Absolute Resolve.

Several bills in Congress aim to restrict prediction-market trading by officials. In January Representative Ritchie Torres introduced the Public Integrity in Financial Prediction Markets Act of 2026 to bar federal officials from trading on such platforms. In March Senators Jeff Merkley and Amy Klobuchar filed legislation to prohibit senior executive-branch officials from trading. Representatives Blake Moore and Salud Carbajal put forward a bipartisan bill targeting insider trading tied to sensitive military secrets and democratic processes.

Other proposals seek to limit markets that reference sports wagering, terrorism, assassination, war or the death of an individual.

Some state and private employers have issued similar rules. Illinois Governor J.B. Pritzker directed state employees not to use insider information to bet on prediction markets.

Polymarket, the platform that drew recent scrutiny, responded online. Olivia Chalos, the company’s deputy chief legal officer, wrote 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 concerns about national security and market integrity. Senator Richard Blumenthal criticized the platform for permitting markets tied to national security secrets and pointed to a market about a possible rescue of a U.S. soldier in Iran.

Lawmakers said attention grew after anonymous bettors placed timely, profitable trades ahead of major public announcements. The Senate rule change is one of several legislative and institutional actions to clarify how existing securities and derivatives rules apply to online prediction markets.