The Supreme Court handed down a significant decision on Tuesday, ruling that President Donald Trump's deployment of National Guard troops to quell protests outside an immigration detention facility in Broadview, Illinois, was a violation of federal law. In a 6-3 decision, the court found that Trump's actions exceeded his authority as commander-in-chief and infringed on the rights of protesters.

According to court documents, Trump had deployed a few hundred members of the National Guard to the facility in response to protests by immigration advocates and other groups. The protesters had been demonstrating against the detention of migrants at the facility, which is operated by Immigration and Customs Enforcement (ICE). The court found that Trump's decision to deploy the National Guard was a misuse of his authority and a violation of the Posse Comitatus Act, which prohibits the use of federal troops for law enforcement purposes within the United States.

Justice Stephen Breyer, writing for the majority, stated that "the deployment of National Guard troops to quell protests is a serious matter that requires careful consideration and adherence to the law." Breyer noted that while the president has broad authority as commander-in-chief, "that authority is not without limits, and the deployment of troops to quell protests is a significant exercise of that authority that must be carefully considered."

The decision was welcomed by civil liberties groups, who argued that Trump's actions were an overreach of executive power. "Today's decision is a major victory for the rights of protesters and a reminder that the president is not above the law," said a spokesperson for the American Civil Liberties Union (ACLU). "We are pleased that the court has recognized the importance of protecting the rights of protesters and the need for the president to adhere to the law."

The decision was also seen as a significant setback for Trump, who had been seeking to expand his authority as president. Trump's lawyers had argued that the deployment of National Guard troops was necessary to maintain order and protect the safety of protesters, but the court rejected that argument.

The decision is the latest in a series of high-profile cases involving Trump's use of executive power. In 2020, the Supreme Court ruled that Trump's decision to terminate the Deferred Action for Childhood Arrivals (DACA) program was unlawful, and in 2022, the court found that Trump's actions in the January 6, 2021, insurrection were a serious abuse of power.

The decision is expected to have significant implications for future presidential actions, particularly with regards to the use of military force and the protection of civil liberties. As one legal expert noted, "this decision sends a clear message that the president is not above the law and that the courts will carefully scrutinize any attempts to expand executive power."