Congress Bans Members From Betting on Prediction Markets After Insider Trading Case

Published by James Harris on June 19, 2026June 19, 2026

A House Republican introduced legislation Thursday that would prohibit members of Congress, their spouses, and dependent children from placing bets on prediction markets tied to government policy, legislation, or political outcomes. The bill targets platforms like Kalshi and Polymarket directly, and it carries real teeth: violators cannot cover fines through office accounts or campaign funds, and the Justice Department can pursue unpaid penalties civilly even after someone leaves Congress.

The timing is not accidental. A federal case involving Army soldier Gannon Ken Van Dyke, charged with using confidential military intelligence to win roughly $400,000 on a Polymarket bet about Venezuelan President Nicolas Maduro, handed lawmakers a concrete example of what insider bets on prediction markets actually look like when they go wrong. The Senate passed a blanket ban on senator participation by unanimous consent in late April, and a House version followed from Rep. Ashley Hinson before Speaker Mike Johnson slowed things down, citing the need for broader buy-in. Steil’s bill is the result of that deliberate process, framed explicitly as an extension of the Stop Insider Trading Act his committee advanced in January rather than a reaction to a single news cycle.

Congress writing prediction market rules while holding advance knowledge of the outcomes those markets price is not a hypothetical conflict. It is the structural problem.

The bill’s carve-out for sports betting and activities unrelated to official duties matters for how platforms like Kalshi operate commercially, since the CFTC has already spent considerable energy defining which event contracts are permissible and which cross into territory regulators will not allow. A congressional restriction layered on top of that existing regulatory framework creates a two-track compliance environment: one track for what the CFTC permits the platforms to offer, another for what elected officials are personally allowed to touch. Prediction market operators will need to think carefully about whether any verification or flagging obligations attach to the congressional prohibition, or whether enforcement falls entirely on the members themselves.

Steil’s framing connects this explicitly to the congressional stock trading debate, which has cycled through Congress for years without producing a durable, comprehensive law. That precedent suggests the harder question is not whether this bill passes committee but whether it survives the same political friction that has repeatedly stalled broader insider trading reform. Johnson’s support and Trump’s backing of the companion stock trading bill improve the odds, but the pattern of incremental advancement followed by floor-scheduling delays is familiar enough to temper expectations.