Detroit Joins Michigan's Fight vs Coinbase Markets

Coinbase prediction markets may be a tech-forward product, but the fight over who gets to regulate them is looking a lot like old-fashioned turf warfare. On Thursday, District Judge Shalina Kumar approved an order allowing attorneys representing the city of Detroit to file an amicus brief in Coinbase's lawsuit against Michigan — putting the Motor City squarely on the side of state gambling regulators who want to keep the crypto exchange's prediction market product off Michigan's digital streets.

How Detroit Got Into This Courtroom

The case stems from Coinbase filing its lawsuit against the state of Michigan back in December 2025 — notably more than a month before the exchange formally announced the public launch of its Coinbase prediction markets product. That pre-emptive legal strike was a calculated move: get a federal court to rule on jurisdiction before state regulators could shut you down.

Coinbase sued gaming authorities in Connecticut and Illinois at the same time, building a multi-front legal campaign rooted in one central argument — that prediction markets are event contracts regulated by the US Commodity Futures Trading Commission, not gambling products subject to state casino law. The company is betting that federal preemption wins the day. Michigan's gaming board disagrees. Loudly.

District Judge Shalina Kumar's Thursday ruling in the US District Court for the Eastern District of Michigan greenlights Detroit's entry into the fray. Detroit's lawyers now have until April 3 to file the brief in connection with state officials' motion for a preliminary injunction — effectively asking the court to pause Coinbase's operations pending a full trial.

Why Does Detroit Care About Crypto Prediction Bets?

Why is Detroit filing an amicus brief in the Coinbase Michigan lawsuit?

Detroit's interest here isn't abstract. The Michigan Gaming Control Board reported that Detroit-based casinos generated more than $200 million in combined revenue during January and February alone — and that windfall produced over $24 million in taxes flowing directly to the state. That's the number you need to keep in your head when reading any of the high-minded language about "regulatory jurisdiction" in this case.

Prediction markets — where users bet on outcomes like election results, economic indicators, or sports events — compete directly with the kinds of products that brick-and-mortar and online casinos offer. If a federal court rules that these platforms operate solely under CFTC authority, state regulators lose their ability to block or tax them. For a city that runs on casino revenue, that's not a legal nuance. That's an existential threat to a revenue stream.

So Detroit filing in support of Michigan's gaming board isn't a surprise. It's a follow-the-money play dressed in amicus brief clothing.

The more the CFTC can do in this space to put a comprehensive regulatory regime around it, the more likely it is for courts who are looking at the issue to say 'actually, yes, this is a CFTC jurisdiction issue — this really is not just an end run around sports gambling bans in particular states.'

The CFTC vs. States Standoff — Where Does It Go?

The broader legal landscape here is messy. CFTC prediction markets regulation has been a moving target — CFTC Chair Michael Selig has proposed new rules staking out commission authority over event contracts, but the proposals haven't translated into clear legal protection for platforms. Courts are still figuring this out case by case, state by state.

Stephen Piepgrass, a partner at Troutman Pepper Locke, told reporters the whole thing could eventually land back at the US Supreme Court — citing the 2018 decision in Murphy v. National Collegiate Athletic Association, which handed states the authority to regulate sports gambling by striking down a federal prohibition. If the Supreme Court applied similar logic here, it would be a significant blow to platforms like Coinbase, Kalshi, and Polymarket, all of which are currently fighting Michigan lawsuit Coinbase-style battles in multiple jurisdictions.

The outcomes so far cut both ways. A Nevada judge ordered Kalshi to temporarily halt operations in that state this month, and the platform is facing criminal charges in Arizona over alleged illegal gambling on sports and election outcomes. But a Tennessee judge blocked state authorities in February from enforcing gambling laws against Kalshi at all — same product, opposite result, different courtroom. That kind of split is exactly what makes Supreme Court review more likely, not less.

Eleven states are now involved in legal battles against prediction market platforms in various forms. The patchwork is unsustainable — at some point, either Congress acts, the CFTC gets a clear mandate, or the Supreme Court steps in. What we're watching in Michigan right now is one node in a much larger national argument about who controls the future of event-based betting in America.