Steil Introduces Bill to Restrict Congressional Prediction Market Trades
A new legislative proposal making its way through the House of Representatives could fundamentally change how members of Congress and their families are permitted to interact with financial prediction markets. House Administration Committee Chairman Bryan Steil introduced the Stop Lawmakers from Predicting Act on June 18, targeting a growing concern about the intersection of political insider knowledge and speculative trading platforms.
The bill would prohibit members of Congress and their immediate family members from participating in certain prediction market trades — specifically those tied to government decisions, political developments, or information obtained through the privilege of public service. As prediction markets surge in popularity and mainstream legitimacy, the proposal has sparked a renewed conversation about government ethics, financial conflicts of interest, and the integrity of democratic institutions.
What Is the Stop Lawmakers from Predicting Act?
The Stop Lawmakers from Predicting Act is a focused piece of legislation designed to close what many ethics watchdogs consider a significant loophole in existing congressional financial disclosure and trading rules. While prior legislative efforts such as the STOCK Act addressed stock trading by members of Congress, prediction markets — platforms where users place wagers on the outcomes of real-world events — have largely fallen outside the scope of those restrictions.
Prediction markets have evolved from niche financial instruments into widely used platforms where participants can bet on political outcomes, legislative results, regulatory decisions, and electoral races. Sites like Kalshi and Polymarket allow users to trade contracts based on whether specific events will occur, making them particularly sensitive when those events happen to be directly influenced by the very lawmakers who might be placing trades.
Chairman Steil's bill would close this gap by explicitly barring members of Congress and their immediate families from using nonpublic information — or the privileged access that comes with holding elected office — to gain an advantage in these markets.
Why Prediction Markets Raise Unique Ethics Concerns for Lawmakers
Traditional stock market trading restrictions for Congress exist because lawmakers often have advance knowledge of legislation, regulatory changes, or government contracts that could affect a company's value. The same logic applies — and arguably with even greater force — to prediction markets, where the traded asset is the outcome of a political or governmental event itself.
Consider a member of Congress sitting on a committee that is drafting significant healthcare legislation. That lawmaker would have early knowledge of whether a bill is likely to pass, what its contents might be, and how it could affect various sectors of the economy. A prediction market contract asking "Will Congress pass a major healthcare bill this session?" would be extraordinarily sensitive to exactly the kind of information that lawmaker holds.
Critics of unregulated congressional participation in prediction markets argue that this creates a scenario where elected officials could effectively profit from the outcomes of their own decisions — or from their advance knowledge of others' decisions — in ways the public cannot easily monitor or challenge.
The Growing Popularity of Political Prediction Markets
The timing of Steil's proposal is no coincidence. Prediction markets have experienced explosive growth in recent years, particularly following high-profile electoral cycles where platforms like Polymarket attracted tens of millions of dollars in trading volume around U.S. presidential and congressional elections. In 2024, these platforms became mainstream news fixtures, cited alongside traditional polling as indicators of electoral sentiment.
The Commodity Futures Trading Commission (CFTC) has also been navigating how to regulate event contracts tied to political outcomes, with some platforms receiving approval to offer election-related contracts to U.S. customers. As the regulatory landscape has gradually opened up, the volume and visibility of politically linked prediction market activity has increased substantially — bringing with it heightened scrutiny of who is trading and on what basis.
For ordinary citizens, participation in these markets is a form of speculative entertainment or investment. For a sitting U.S. lawmaker with access to nonpublic deliberations, committee proceedings, and advance policy intelligence, participation raises far more serious questions.
Congressional Trading Restrictions: A Broader Context
The Stop Lawmakers from Predicting Act fits within a broader and ongoing debate about financial conflicts of interest in Congress. The STOCK Act, passed in 2012, required members of Congress to disclose trades in individual securities and prohibited trading on material nonpublic information. However, enforcement has been widely criticized as lax, with many disclosure deadlines routinely missed and penalties considered insufficiently deterrent.
Several bills aimed at banning congressional stock trading outright have been introduced in recent years, reflecting bipartisan public frustration with the perception — and in some documented cases, the reality — that lawmakers trade stocks in ways that benefit from their privileged positions. While comprehensive stock trading bans have not yet cleared Congress, the Steil bill signals continued legislative appetite for expanding and updating ethics rules in response to new financial instruments.
What Happens Next?
The Stop Lawmakers from Predicting Act has been referred for consideration following its June 18 introduction. Whether it advances through committee and to a floor vote will depend on the level of bipartisan support it can attract. Ethics reform legislation often faces resistance, even when the underlying principle enjoys broad public approval, due to the obvious personal interests of those being asked to vote on their own restrictions.
Advocacy groups focused on government transparency and ethics reform have generally welcomed the proposal as a necessary update to congressional financial conduct rules. Public polling consistently shows that Americans across party lines support stronger restrictions on how members of Congress can use their positions for personal financial gain.
The Bottom Line
Rep. Bryan Steil's Stop Lawmakers from Predicting Act represents a targeted and timely legislative response to an emerging ethics challenge. As prediction markets become a mainstream feature of the American financial landscape, ensuring that members of Congress cannot exploit their unique access to information or governmental power to gain an unfair trading advantage is a matter of basic democratic integrity. The bill's fate in Congress will be an important test of whether lawmakers are willing to apply meaningful ethics guardrails to their own financial conduct in the digital age.