War fever heightens.

The Trump administration has opened a criminal investigation into elected Democrats in Minnesota, according to a senior law enforcement official familiar with the matter, a major escalation in the fight between the federal government and local officials over the aggressive immigration crackdown underway in the city.

Or to put it another way, Trump and his administration are treating a disagreement about immigration policy as a criminal matter. We know that Trump thinks it’s a crime to dispute his assertions, but we get a little edgy when he says it out loud.

The investigation would focus on allegations that Gov. Tim Walz and Jacob Frey, the mayor of Minneapolis, had conspired to impede thousands of federal agents who have been sent to the city since last month. Last week, one of those agents killed a 37-year-old woman, Renee Good.

Or to put it another way, Trump and his hirelings have conspired to violate the human rights of thousands of immigrants and their neighbors since last month.

“Weaponizing the justice system and threatening political opponents is a dangerous, authoritarian tactic,” Mr. Walz said in a statement released by his office, which said it had not yet received notice of an investigation. “The only person not being investigated for the shooting of Renee Good is the federal agent who shot her.”

Mr. Frey described the investigation as an “obvious attempt to intimidate” him, but vowed it would not work.

Unless Trump and co make it work, by whatever means they can find. We know they’re not going to fret about laws or constitutionality.

News of the investigation, which was reported earlier by CBS News, came only two days after Todd Blanche, the deputy attorney general, posted an incendiary message on social media, accusing Mr. Walz and Mr. Frey of “encouraging violence against law enforcement” and referring to their actions as “terrorism.”

While both the governor and the mayor have criticized agents involved in the immigration crackdown and have at times urged local residents to document their actions, there is no public evidence that either man has explicitly encouraged violence — let alone engaged in acts of terrorism. Both have urged protesters to remain peaceful.

Yes but all Trump and co have to do is interpret criticism of agents as terrorism, and there’s your explicit encouragement of terrorism.

Federal officials have already signaled that they are not likely to bring criminal charges against Jonathan Ross, the agent who killed Ms. Good. At the same time, the officials have said that law enforcement would most likely investigate Ms. Good’s partner, Becca Good, and any possible connections the women might have had to local activists.

That decision prompted at least six federal prosecutors to resign this week from the U.S. attorney’s office in Minneapolis.

Federal officials are only as good as the Big Boss lets them be.