WASHINGTON — Acknowledging that lawmakers are often privy to sensitive information, the Senate unanimously approved a bipartisan resolution Thursday to ban its members, officers and staff from placing wagers in prediction markets.
The move came one week after a U.S. soldier was charged with using classified information to bet on the ousting of Venezuela’s then-President Nicolas Maduro in January.
“United States Senators have no business engaging in speculative activities like prediction markets while collecting a taxpayer-funded paycheck, period,” resolution sponsor Sen. Bernie Moreno, R-Ohio, said in a statement Thursday. “Serving in Congress should never be about finding new ways to profit; it should be about delivering results for the American people.”
Prediction markets are open trading platforms that let participants sell and buy contracts based on the outcomes of future events, including elections, sporting events and the weather. Top platforms include Polymarket and Kalshi, which have come under fire in recent months as lawmakers on both sides of the aisle contend they promote insider trading and lead to national security risks.
“We must never allow Congress to turn into a casino where members representing the public can gamble on wars or economic crises or elections,” Senate Minority Leader Chuck Schumer, D-N.Y., said on the Senate floor Thursday. “That would destroy the very principle of representative government.”
Following the Senate vote to ban its members from prediction market betting, Rep. Ashley Hinson, R-Iowa, announced she would lead a similar effort in the House of Representatives, writing on X, “Let’s get it done.”
During a hearing of the Senate Armed Services Committee on Thursday, Sen. Elizabeth Warren, D-Mass., repeatedly asked Defense Secretary Pete Hegseth if Trump administration officials were engaged in possible insider trading and placing prediction market bets on the Iran war.
“Americans are paying a high price for Donald Trump’s war with Iran: 14 service members dead, over 400 more wounded, prices rising for nearly every American family,” Warren said during the hearing. “But someone is profiting off Trump’s war — insiders who know what’s going on and who place bets on that inside information.”
The Trump administration has been a key ally of the growing prediction market industry in a legal fight with states seeking to ban the platforms. Donald Trump Jr., the president’s eldest son, is an adviser for both Polymarket and Kalshi.
Warren said that on March 23, minutes before Trump posted on Truth Social that there had been “very good conversations” about ending the war with Iran, traders bet $500 million on the price of oil, which immediately dropped after Trump’s post.
In April, The Associated Press reported that a group of new accounts on Polymarket made highly specific, well-timed bets on whether the United States and Iran would reach a ceasefire on April 7, resulting in hundreds of thousands of dollars in profits for the new customers.
When Warren asked Hegseth to provide an explanation for “perfectly timed spikes in trading activity” concerning the Iran war, he said his department is “focused on our mission of executing for the American people. And what happens in markets is not, in betting markets, is not something we’re involved in.”
The Associated Press contributed to this report.