Hours after an immigration agent fatally shot Renee Good inside her SUV on a Minneapolis street last month, a senior federal prosecutor in Minnesota sought a warrant to search the vehicle for evidence in what he expected would be a standard civil rights investigation into the agent’s use of force.

The prosecutor, Joseph H. Thompson, wrote in an email to colleagues that the Minnesota Bureau of Criminal Apprehension, a state agency that specialises in investigating police shootings, would team up with the FBI to determine whether the shooting had been justified and lawful or had violated Good’s civil rights.

But later that week, as FBI agents equipped with a signed warrant prepared to document blood spatter and bullet holes in Good’s SUV, they received orders to stop, according to several people with knowledge of the events who spoke on the condition of anonymity because they were not authorised to speak publicly.

The orders, they said, came from senior officials, including Kash Patel, the FBI director, several of whom worried that pursuing a civil rights investigation — by using a warrant obtained on that basis — would contradict President Trump’s claim that Good “violently, willfully, and viciously ran over the ICE officer” who fired at her as she drove her vehicle.

Over the next few days, top officials of the justice department presented alternative approaches. First, they suggested prosecutors ask a judge to sign a new search warrant for the vehicle, predicated on a criminal investigation into whether the US immigration and customs enforcement agent who shot Good, Jonathan Ross, had been assaulted by her. Later, they urged the prosecutors to instead investigate Good’s partner, who had been with Good on the morning of the shooting, confronting immigration agents in their Minneapolis neighbourhood.

Several of the career federal prosecutors in Minnesota, including Thompson, baulked at the new approach, which they viewed as legally dubious and incendiary in a state where anger over a federal immigration crackdown was already boiling over. Thompson and five others left the office in protest, setting off a broader wave of resignations that has left Minnesota’s US attorney’s office severely understaffed and in crisis. Officials have not said whether they ultimately obtained a new warrant to search the vehicle.

From an office of about 25 criminal litigators, gone are the top prosecutors who had overseen a sprawling, years-long investigation into fraud in Minnesota’s social services programmes, which the White House months ago cited as a reason for the immigration crackdown in the state.

The departures have also drained the US attorney’s office as it prepares complex cases, including trials in the fatal attack on a Minnesota state lawmaker and in a terrorism case, and investigations into fentanyl trafficking.

The prosecutors who remain have been flooded with new cases related to the immigration crackdown — allegations of assaults on federal officers and lawsuits challenging the legality of individual detentions of immigrants.

“This is potentially destroying all of the progress that we have made, working together between local and federal law enforcement officials in a very coordinated way, to actually go after the worst of the worst,” Brian O’Hara, the Minneapolis police chief, said in an interview.

New York Times News Service