Arizona went further against Kalshi than any other state, filing actual criminal charges rather than the cease-and-desist letters or civil suits used elsewhere. It did not hold. A federal court blocked the prosecution, siding with the federal commodities regulator, and Arizona’s case stalled before it could reach a trial.

But a later appeals-court ruling in a neighboring state has since put that block on far shakier ground. Smart Bet Insider tracks prediction markets and the legal fights reshaping them state by state. The sections below cover how Arizona escalated, the criminal charges, the CFTC’s countersuit, the federal block, and where the fight stands now.

How Arizona Turned it Up a Notch

The dispute began conventionally enough, with Arizona’s Department of Gaming sending Kalshi a cease-and-desist letter in May 2025 over its event contracts. Where other states stuck to letters or civil enforcement, Arizona chose a far sharper path.

Anticipating the escalation, Kalshi sued Arizona’s gaming regulator in federal court on March 12, 2026, arguing the state was intruding on the federal government’s exclusive authority to regulate derivatives trading. Days later, Arizona answered not with a civil filing but with a criminal case, setting up the most aggressive state-versus-Kalshi confrontation in the country.

The Criminal Charges

On March 17, 2026, Attorney General Kris Mayes filed the first criminal charges brought by a state against a CFTC-registered prediction market. The 20-count criminal information, filed in Maricopa County Superior Court, accused Kalshi of running an illegal gambling operation and operating without the licensure Arizona law requires.

The counts reached beyond sports. Four were tied to election wagering, including contracts on the 2028 presidential race and several 2026 Arizona state races, while others targeted college sports and individual player-performance markets. By invoking Arizona’s broad definition of wagering, the case took aim at the entire event-contract model rather than sports products alone.

The CFTC Countersuit

The federal government responded forcefully. On April 2, 2026, the Commodity Futures Trading Commission sued Arizona, along with Connecticut and Illinois, arguing that the Commodity Exchange Act expressly preempts state gaming laws as applied to CFTC-regulated markets.

The agency went further than defending Kalshi, asking the court to declare state gambling laws invalid as applied to prediction markets and accusing Arizona of intruding on its exclusive federal authority. CFTC Chairman Michael Selig publicly backed the challenge, framing Arizona’s criminal approach as a dangerous precedent against firms complying with federal rules.

The Federal Block

The courts moved quickly in the CFTC’s favor. On April 10, Judge Michael Liburdi granted a temporary restraining order after finding the CFTC likely to succeed on its preemption claim, warning that Arizona’s prosecution might violate the Supremacy Clause of the Constitution.

Then on May 5, the same judge issued a longer-term injunction blocking Arizona from pursuing criminal or civil enforcement against contracts listed on CFTC-regulated exchanges, effectively halting the state’s criminal case in district court. Mayes’ office said it was evaluating its legal options but did not immediately commit to an appeal.

Where Things Currently Stand 

At the district-court level, the outcome was a clear win for Kalshi, since the federal block stopped Arizona’s prosecution and endorsed the CFTC’s preemption argument. For a time, that made Arizona a leading example of federal authority overriding state gambling enforcement.

That footing has since weakened. Arizona sits within the Ninth Circuit, and the Ninth Circuit later ruled in a Nevada case that the Commodity Exchange Act does not preempt state gambling law as applied to sports contracts, the opposite of the reasoning Arizona’s block rested on. That conflict leaves the Arizona injunction vulnerable and the broader question likely bound for the Supreme Court.

The Bigger Picture

Arizona became the sharpest test of whether a state can criminally prosecute a federally regulated prediction market, and for now the answer from the district court is no. Yet the ground has shifted beneath that ruling, so the block that once looked decisive may not survive the appellate landscape that has formed around it.

Smart Bet Insider tracks prediction markets and the legal battles shaping their future in Arizona and across the country. Check the coverage before assuming any single ruling is final, because this area of law is moving quickly and higher courts could still reshape it. None of this is legal advice, and anyone with a specific question should consult an attorney licensed in Arizona.

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Frequently Asked Questions

What happened in the Kalshi Arizona lawsuit?

Arizona became the first state to file criminal charges against Kalshi, with Attorney General Kris Mayes bringing a 20-count criminal case in March 2026 alleging illegal gambling. The CFTC then sued Arizona, and a federal judge blocked the prosecution, ruling that federal law likely preempts state gambling law as applied to CFTC-regulated exchanges. The block halted Arizona’s case in district court.

Why did Arizona file criminal charges against Kalshi?

Arizona’s attorney general argued that Kalshi’s event contracts are illegal, unlicensed gambling under state law, including bets on elections and sports. Unlike other states that sent cease-and-desist letters or filed civil suits, Arizona pursued a criminal case. The charges targeted the entire event-contract model, not just sports markets.

What was the CFTC’s role in the Arizona case?

The Commodity Futures Trading Commission sued Arizona in April 2026, along with Connecticut and Illinois, arguing that federal law gives it exclusive authority over prediction markets. It asked the court to declare state gambling laws invalid as applied to these platforms. The agency’s intervention was central to the federal court blocking Arizona’s prosecution.

Did the federal court permanently stop Arizona’s case?

A federal judge issued an injunction on May 5, 2026, blocking Arizona from enforcing its gambling laws against Kalshi’s CFTC-listed contracts, which halted the criminal case in district court. Reporting differed on whether the order was styled as preliminary or permanent. Either way, a later Ninth Circuit ruling has since cast doubt on the reasoning behind it.

Is Kalshi legal in Arizona now?

For the moment, Arizona cannot prosecute Kalshi because of the federal injunction, so the platform is not facing active enforcement there. However, the Ninth Circuit later ruled against Kalshi’s preemption argument for sports contracts in a Nevada case, which undermines the Arizona block. The situation remains unsettled and could change on appeal.