Representative James Comer, chair of the House Oversight and Government Reform Committee, initiated a congressional probe into insider trading on prediction markets on May 22. The investigation focuses on platforms including Polymarket and Kalshi, with initial document requests sent to their leadership regarding compliance and trading logs.
Investigators discovered over 80 suspicious trades on Polymarket linked to geopolitical events. One user achieved a 93% success rate on wagers concerning US military actions in Iran, earning nearly $1 million. Another notable case involves Army Master Sgt. Gannon Ken Van Dyke, indicted in April 2026 for allegedly profiting $409 881 using classified data.
Comer intends to introduce legislation prohibiting government employees from using non-public information for trading on prediction markets. While current ethics rules restrict the use of classified data, these platforms currently operate in a regulatory gray area. The Commodity Futures Trading Commission has only recently started establishing oversight for such services.
