Detroit lawyers moved to support Michigan in Coinbase’s federal lawsuit over prediction markets, adding a city voice to a case that already centers on state authority and federal oversight. The dispute does not target all of Coinbase’s business in Michigan. Instead, it focuses on whether Coinbase’s prediction markets fall under federal commodities law or state gambling rules.
Coinbase filed the lawsuit on Dec. 18, 2025, in the U.S. District Court for the Eastern District of Michigan. Court records show the case is titled Coinbase Financial Markets, Inc. v. Nessel, and it challenges Michigan’s attempt to treat the company’s prediction markets as gambling activity.
The latest development is new, but only as a case update. Reports point to a March 26 court order that allowed Detroit to file an amicus brief. So, the article is new, while the legal step it describes is part of an older case that has been active since December.
Court Order Adds Detroit to the Case
The court order does not say Detroit already filed the brief. Instead, it says Detroit may submit an amicus curiae brief by April 3, 2026. That matters because some headlines make it sound like the filing is already on the docket, while the order itself only grants permission.
That distinction changes the framing. At this stage, Detroit has been cleared to support Michigan’s position, but the legal record still turns on what the city actually files and how the court treats that argument. Therefore, the development is procedural, not a final ruling on the merits.
The case is part of a wider fight over prediction markets in the United States. Coinbase has argued that these contracts should fall under CFTC oversight, while states have argued they can regulate them as gambling products when they involve local betting rules and consumer protections.
Why Detroit Joined Michigan’s Side
Detroit’s interest appears tied to the city’s gaming economy. Michigan regulators said Detroit’s three commercial casinos reported $100.6 million in aggregate February 2026 revenue. In a separate state update, regulators said the casinos paid $13.4 million in wagering taxes and municipal services fees to the City of Detroit during that month.
That financial backdrop helps explain why Detroit would support Michigan’s argument. If prediction markets expand outside the state’s gambling structure, city officials may see them as a challenge to a regulated system that already produces tax revenue and local fees. The city’s move, therefore, adds an economic angle to a legal fight that has mostly been framed around jurisdiction.
The broader point is clear. This is not a fresh lawsuit, and it is not an effort to ban Coinbase as a whole. It is a new step in an existing case over prediction markets, and Detroit’s entry shows that the dispute now reaches beyond state regulators to local governments with direct gaming revenue at stake.
Source: https://coinpaper.com/15805/detroit-backs-michigan-in-coinbase-prediction-market-fight