Senators ban themselves from prediction markets after candidates bet on own races

US senators voted unanimously to ban themselves from making bets on prediction markets yesterday, about a week after Kalshi said it caught three congressional candidates betting on their own campaigns.

The resolution to prohibit senators from trading on prediction markets passed yesterday by unanimous consent. The action amends the Senate’s conflict-of-interest rules and does not require approval by the House of Representatives. The House has a pending resolution that would impose a similar rule on its own members.

“United States Senators have no business engaging in speculative activities like prediction markets while collecting a taxpayer-funded paycheck, period,” said Sen. Bernie Moreno (R-Ohio), who introduced the resolution. “Serving in Congress should never be about finding new ways to profit; it should be about delivering results for the American people.”

Moreno’s resolution applies broadly to all bets on prediction markets, not just those related to events of which a senator has inside knowledge. The Senate also adopted an amendment submitted by Sen. Alex Padilla (D-Calif.), which extends the trading ban to Senate officers and employees. Padilla said in a statement that the rule as amended “is a commonsense step to ensure that senators and their staff cannot use their positions of public trust to line their own pockets.”

Senate ethics rules are enforced by the Senate Ethics Committee, but the Senate’s enforcement process has been described as being much less effective than the House equivalent.

Democrat wants bill targeting Trump admin corruption

Padilla also said he is pushing “for legislation to rein in Trump administration officials who may be profiting off insider knowledge, including military operations.” A US Army soldier was recently arrested for insider trading after being accused of making prediction-market wagers on the timing of the military’s capture of Venezuelan President Nicolás Maduro.

“Politicians betting on their own races, massive wagers placed moments before the president announced of a ceasefire in Iran, and suspected insider trading before the capture of Nicolás Maduro—these are just a few examples of the blatant, brazen corruption that we’ve seen playing out on prediction markets,” Padilla said.

Padilla added, “This resolution alone will not address the growing public outrage over the unprecedented scale of corruption under the Trump administration.” Major prediction markets Polymarket and Kalshi both have Donald Trump Jr. as an advisor, and a Trump Jr.-backed venture capital firm invested in Polymarket.

Kalshi and Polymarket both said they support the Senate resolution and that they already banned such trading in their platform rules. Kalshi last week announced enforcement actions against two House candidates and one Senate candidate who bet on their campaigns.

Kalshi fines candidates

Kalshi has an extensive rulebook that allows it to impose fines, bans, and suspensions on traders. Two of the three candidates agreed to settlements with Kalshi. Democrat Matt Klein, a House candidate in Minnesota, agreed to a five-year suspension and fine of $539.85. Republican Ezekiel Enriquez, a House candidate in Texas who lost in the primary, agreed to a five-year suspension and $784.20 fine.

Klein, who has since co-authored a Minnesota state Senate bill to prohibit prediction markets, said he made the bet in October 2025 because he was curious about how prediction markets worked. “I set up an account and bet $50 of my own funds that I would win the primary,” he wrote. “I was informed in March of 2026 that this was a violation of the platform rules. In compliance with their request, I paid a penalty and agreed to be suspended from the platform.”