Trump-Newsom Legal Showdown: Battle Over Constitutional Powers and Posse Comitatus Act in California Immigration Raids Dispute

A court hearing will take place on Monday between attorneys representing President Donald Trump and California Governor Gavin Newsom, aiming to determine if the president breached a 147-year-old law by deploying the National Guard to manage protests in Los Angeles over immigration raids, against the wishes of the Democratic governor.

In June, demonstrations erupted in Los Angeles following a series of immigration raids that targeted workplaces and resulted in several detentions and deportations. In response, President Trump federalized 4,000 National Guard members, despite objections from Newsom and local officials who argued the deployment would exacerbate chaos. The president invoked an infrequently used law that enables the president to federalize the National Guard during times of actual or imminent rebellion, invasion, or when regular forces are unable to enforce U.S. laws.

The president’s legal team maintained in a court filing that the roles and responsibilities of the National Guard troops and dispatched Marines were strictly defined: they were sent solely to protect federal property and personnel, and did not engage in any law enforcement activities.

Governor Newsom filed a lawsuit on June 9 against Trump and Defense Secretary Mark Esper, claiming they violated the Posse Comitatus Act and the 10th Amendment. The president’s legal team argues that the act does not offer provisions for a private civil lawsuit.

However, Newsom’s lawyers contend that the president unlawfully seized power by overriding local authorities to send in the military, potentially even contravening the Constitution. They argue that Trump and Esper have exceeded their legal bounds by using the military in unprecedented, unlawful ways, as outlined in the complaint.

The court hearing is a significant moment for determining how much power a U.S. president can lawfully exercise over the military on domestic soil. Throughout his first term, Trump had openly speculated about deploying the military domestically, whether to quell protests or combat crime. Recently, he has discussed deploying the National Guard to the nation’s capital in response to high-profile crimes.

The court hearing also marks an intensification of the dispute between Trump and Newsom, which escalated during the Los Angeles protests when the president threatened to have the Democratic governor arrested. Newsom described this comment as “an unmistakable step toward authoritarianism.”

U.S. District Court Judge Charles R. Breyer previously granted a temporary restraining order against the Trump administration, ruling that the president illegally federalized the National Guard and that the protests did not amount to an insurrection. However, just hours later, an appeals court suspended his ruling, allowing the deployment to continue.

The trial is taking place in San Francisco, presided over by Breyer, with proceedings scheduled from Monday to Wednesday. At the core of the legal proceedings is the Posse Comitatus Act, which primarily prohibits the president from using the military as a domestic police force.

The act, enacted by President Rutherford B. Hayes in 1878, stipulates that anyone who “willfully uses any part of the Army or the Air Force as a posse comitatus” or otherwise to enforce laws will be fined or imprisoned for up to two years, or both. Newsom’s legal team argues that the deployment of the National Guard in Los Angeles violated this act because it prohibits the military from engaging in civil law enforcement unless explicitly authorized by law.

Trump’s lawyers counter that the National Guard and Marines did not engage in any civil law enforcement, therefore did not breach the act. Furthermore, they argue that the act does not provide mechanisms for its enforcement in a private civil lawsuit.

Newsom’s legal team also alleges that Trump violated the 10th Amendment of the Constitution by overriding California officials and the Administrative Procedure Act by issuing orders without the consent or consultation of Governor Newsom. The trial will delve into these claims, as well as the compliance of the National Guard with the Posse Comitatus Act.