Ruling represents setback for investigation that targeted state Democratic officials who criticised immigration raids.

A United States judge has blocked efforts by the administration of US President Donald Trump to subpoena Democratic state officials in the Midwestern state of Minnesota, a setback for the government’s efforts to investigate officials who voiced opposition to the government’s mass deportation raids.

US District Judge Patrick Schiltz quashed subpoenas issued against officials such as Governor Tim Walz, part of a Department of Justice (DOJ) probe launched during the height of the crackdown, in a ruling on Monday.

“The Court finds that the dominant purpose of the challenged subpoenas is to coerce Minnesota officials into assisting the federal government with enforcing civil immigration law and to harass and retaliate against them for failing to do so,” Schiltz wrote in his decision. The order was issued on June 17 and unsealed on Monday.

The Trump administration has faced persistent criticism that it is using threats of prosecutions and investigations to target perceived political enemies and domestic opponents.

The subpoenas, issued against six state officials, sought broad information regarding whether their opposition to the administration’s raids constituted an effort to impede federal authorities. The Trump administration recently announced charges against 15 Minnesota activists who were members of an organisation that opposed the raids, citing a directive to “counter domestic terrorism and organised political violence”.

Those raids sparked widespread protests in the state, especially in the aftermath of the fatal shooting of two US citizens by federal agents. State officials decried the raids as a power grab and an effort to intimidate cities seen as centres of resistance to the administration.

Walz, a Democrat who served as the vice presidential candidate for Kamala Harris in the 2024 US presidential election and a frequent target of Trump’s ire, welcomed the ruling in a statement on Monday.

“Today’s ruling is a victory for the rule of law and our democracy. A federal district judge found that the US Department of Justice’s investigation into me and other Minnesota elected officials was politically motivated, unconstitutional, and meritless,” Walz said in a statement shared on social media.

“I will never stop exercising my constitutional rights to stand up for Minnesotans and the American freedoms we hold dear.”