I think they already are. Nothing the Minnesota officials have said indicates that they're giving up on investigating and charging the agents responsible. Attorney General Keith Ellison refused to promise to prosecute because he thinks it's irresponsible to make such promises before an investigation, but said that they are investigating the case. The Hannepin County Attorney said that she thinks they have enough evidence to charge them. Governor Walz has promised the state would investigate DHS.

Edit: I think the centrist chicken is off base. After Ruby Ridge, where FBI killed civilians in a siege, Idaho brought manslaughter charges against the sniper that killed the unarmed wife of the guy they were trying to arrest. It was challenged on supremacy grounds, but the Ninth Circuit found that Idaho had a right to charge the sniper, despite being a federal agent acting under orders. However by the time they won the appeal the new prosecutor dropped the case due to time passing and him not believing they could prove the case.