US district judge blocks Donald Trump’s use of military force to tackle protests against immigration officers.

United States President Donald Trump unlawfully ordered National Guard troops to Portland, Oregon, a federal judge has ruled, marking a legal setback for the president’s use of the military for policing duties in US cities.

The ruling on Friday by US District Judge Karin Immergut is the first to permanently block Trump’s use of military forces to quell protests against immigration authorities.

Immergut, a Trump appointee, rejected the administration’s claim that protesters at an immigration detention facility were waging a rebellion that legally justified sending troops to Portland.

Democrats have said Trump is abusing military powers meant for genuine emergencies such as an invasion or an armed rebellion.

Oregon Attorney General Dan Rayfield described the ruling as a “huge victory” and the “decision confirms that the President cannot send the Guard into Oregon without a legal basis for doing so”.

“The courts are holding this administration accountable to the truth and the rule of law,” Rayfield said in a post on social media.

Portland’s Mayor Keith Wilson also applauded the decision, saying it “vindicates Portland’s position while reaffirming the rule of law that protects our community”.

“As I have said from the beginning, the number of federal troops needed in our city is zero,” Wilson said, according to local media reports.

The City of Portland and the Oregon Attorney General’s Office sued in September, alleging that the Trump administration was exaggerating occasional violence to justify sending in troops under a law permitting presidents to do so in cases of rebellion.

Echoing Trump’s description of Portland as “war-ravaged”, lawyers from the Department of Justice had described a violent siege overwhelming federal agents in the city.

But lawyers for Oregon and Portland said violence has been rare, isolated and contained by local police.

“This case is about whether we are a nation of constitutional law or martial law,” Portland’s lawyer Caroline Turco had said.

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The Trump administration is likely to appeal Friday’s ruling, and the case could ultimately reach the US Supreme Court.

A review by the Reuters news agency of court records found that at least 32 people were charged with federal crimes stemming from the Portland protests since they began in June. Of the 32 charged, 11 pleaded guilty to misdemeanours, and those who have been sentenced received probation.

About half the defendants were charged with assaulting federal officers, including 14 felonies and seven misdemeanours.

Prosecutors dismissed two cases.

Charging documents describe protesters kicking and shoving officers, usually while resisting arrest.

Three judges, including Immergut, have now issued preliminary rulings that Trump’s National Guard deployments are not allowed under the emergency legal authority cited by his administration. (Aljazeera)