Here is the unpublished opinion in State of Wisconsin v. House:

Briefs here.

Public Law 280 is the classic example of what SCOTUS would strike down as violating the anti-commandeering principle of the Tenth Amendment. It is a mandate to states (six of them, including Wisconsin) to assume criminal jurisdiction over Indian country and it’s basically unfounded (more or less like most other aspects of Indian country criminal jurisdiction). I guess since the mandatory PL280 states consent to this federal commandeering of their legislative process, it’s okay? Or since the states retain prosecutorial discretion in individual cases? Like a lot of crap the Supreme Court has been shoving down our collective throats for the last few decades, anti-commandeering law is just stupid with two Os (thank you Knives Out for that one).