Elizabeth Warren Targets Prediction Markets for Crackdown as Senate Banking Chair

Bipartisan Scrutiny Targets Election Betting Platforms

Federal lawmakers are escalating their oversight of political prediction markets following growing concerns over insider activity, illicit wagers, and potential market manipulation. On Oct. 28, Sen. Elizabeth Warren, D-Mass., and Sen. John Curtis, R-Utah, sent a joint inquiry to Kalshi CEO Tarek Mansour and Polymarket CEO Shayne Coplan, demanding answers regarding how their platforms prevent candidates, campaign staff, and individuals holding material nonpublic information from participating in election-related event contracts.

In their communication to the platform executives, the lawmakers emphasized the risks political betting presents to democratic norms:

“We are particularly troubled by election-related event contracts,” the senators wrote. “Event contracts tied to elections receive prominent coverage and are treated by some observers as indicators of political momentum. There are also documented cases of candidates betting on their own races, which undermines the overall integrity of the American electoral process.”

Allegations of Insider Trading and Volume Manipulation

The senators’ inquiry pointed directly to recorded instances of political figures engaging with prediction contracts, citing cases where candidates traded on their own contests on Kalshi, including a February 2026 California gubernatorial race. Furthermore, Warren and Curtis underscored third-party research that alleged wash trading and synthetic volume manipulation on Polymarket. The letter also incorporated findings from an NPR investigation, which revealed campaign insiders admitting to executing trades prior to the public release of proprietary polling data.

Pushing back against the argument that such events are rare, the lawmakers warned of systemic vulnerabilities:

“The identification of isolated instances of improper trading does not demonstrate that these markets are adequately protected,” Warren and Curtis wrote. “Instead, it raises serious questions about how much similar activity may be going undetected.”

The senators set an initial deadline demanding comprehensive written responses from Kalshi and Polymarket by Election Day, Nov. 3.

Addressing compliance concerns, Kalshi head of enforcement Robert DeNault stated to Business Insider that the exchange

“proactively blocks candidates and campaign staff from trading to protect market integrity.”

Polymarket did not respond to requests for comment regarding the bipartisan inquiry.

Regulatory Conflict and the Senate Banking Committee

The regulatory trajectory for these platforms intersects directly with federal oversight of the digital assets industry. Polymarket operates as a crypto-native venue that transitioned toward U.S. access via a Commodity Futures Trading Commission (CFTC)-registered exchange, while Kalshi is formally regulated as a designated contract market under the CFTC. Both entities operate within the jurisdiction of the Senate Banking Committee, an influential panel that Warren is poised to lead.

Under CFTC Chairman Michael S. Selig, the agency spent 2026 legally defending these prediction exchanges against state-level gambling restrictions, filing lawsuits against states including Wisconsin and New York to assert exclusive federal jurisdiction over event contracts on registered exchanges. However, Warren’s looming committee leadership presents a sharp counterweight to federal deregulation, with an aide characterizing the sector as a “Wild West.”

Why This Matters

Senator Warren has consistently stood as one of the most vocal critics of the digital asset industry on Capitol Hill. She previously opposed the CLARITY Act market structure bill, which failed a Senate cloture vote 49-50 on Sept. 15. Market analysts note that a Democratic-led panel significantly narrows the pathway for any future Republican-led market structure revamps, with House Democrats actively preparing alternative legislation designed to grant broader oversight power to the Securities and Exchange Commission (SEC).

Beyond prediction markets, Warren’s broader agenda as chair is slated to encompass economic affordability measures, legislation to cap credit card interest rates, export controls on artificial intelligence chips, and robust investigative oversight of Wall Street executives, Big Tech leadership, Trump administration officials, and individuals connected to the Trump family’s cryptocurrency initiatives. With full subpoena power and the Banking gavel, the primary test for prediction markets will be whether this initial inquiry evolves into formal congressional hearings to fundamentally re-police event-based election trading.

Frequently Asked Questions

What concerns did lawmakers raise about Kalshi and Polymarket?

Senators Elizabeth Warren and John Curtis raised flags over whether platforms are effectively preventing election candidates, campaign operatives, and other insiders with nonpublic data from placing bets on races. They cited issues such as candidates betting on their own elections, insider trades preceding public polling releases, and reports of wash trading and volume manipulation.

How are prediction markets currently regulated in the United States?

Prediction markets fall primarily under federal derivatives oversight. Kalshi operates as a designated contract market regulated by the Commodity Futures Trading Commission (CFTC), and Polymarket aligned U.S. access through a CFTC-registered exchange. The CFTC, led by Chairman Michael S. Selig, has actively challenged state-level gambling enforcement in states like Wisconsin and New York to maintain federal supremacy over event contracts.

How has Kalshi responded to allegations of political insider trading?

Kalshi’s head of enforcement, Robert DeNault, stated that the exchange proactively prevents candidates and campaign personnel from participating in trades on the platform to safeguard market integrity.