LA military deployment ruled unlawful

Summary

On June 7, 2025, Trump signed a memorandum federalizing at least 2,000 California National Guard troops - later raised to 4,000 - and approximately 700 Marines were then sent to Los Angeles to assist with immigration enforcement, over the explicit objection of Governor Gavin Newsom. A federal court ruled on September 2, 2025 that the deployment violated the Posse Comitatus Act of 1878.

What happened

Following protests sparked by ICE raids beginning June 6, Trump issued a June 7 memorandum invoking 10 U.S.C. § 12406 (not the Insurrection Act) to federalize the California National Guard. By June 10, Marines had arrived; Task Force 51 was established with 4,000 National Guard and ~700 Marines at an estimated cost of $134 million. California Governor Newsom filed a legal challenge. On September 2, 2025, U.S. District Judge Charles Breyer ruled the deployment violated the Posse Comitatus Act, finding that federalized troops had engaged in arrests, searches, traffic and crowd control, and other prohibited law enforcement activities. Breyer issued an injunction barring military personnel from those activities.

Impact on the United States

Deployed active-duty military against civilian populations in a U.S. city without Insurrection Act authority, circumventing the constitutional framework requiring congressional authorization. The $134 million cost was borne by taxpayers. The ruling, which applies only to California and was appealed, found the administration had used federalized troops for law enforcement that the Posse Comitatus Act bars.

Documented effects

1. Jun 20254,000 federalized National Guard and ~700 Marines deployed to Los Angeles June 7-10, 2025, at estimated $134 million cost[1]
2. Sep 2025Judge Breyer issued a Posse Comitatus Act injunction on September 2, 2025, barring troop involvement in arrests, searches, and crowd control[2][3]
3. Brennan Center noted the ruling provides a legal framework for states to challenge similar military deployments nationwide[2]
4. Dec 31, 2025Trump announced the National Guard's withdrawal from Los Angeles on December 31, 2025, the same day the Ninth Circuit upheld an order returning control of the troops to Governor Newsom[4]

Why this is rated significant

A federal judge found the use of troops for domestic enforcement violated the Posse Comitatus Act, a significant precedent, though the ruling was appealed, applies only in California, and blocked the activities.

Posse Comitatus injunction Sept 2, 2025, appealed; Guard withdrawn from Los Angeles Dec 31, 2025

Corrections & updates [6]

Every change to a fact on this page after publication is logged here, newest first.

1. Sep 29, 2026CorrectedDate

   Judge Breyer's Posse Comitatus ruling and injunction were issued on September 2, 2025 (ABC News), not September 5. The Brennan Center's analysis of the ruling was published September 5. Also, the June 7 memorandum federalized at least 2,000 Guard troops; a second 2,000 were added later, and the roughly 700 Marines were announced June 9 (PBS).[1][3]

2. Sep 29, 2026ClarifiedSummary

   The Brennan Center notes that Breyer's order applies only to California and was appealed, so it did not establish a nationwide rule.[2]

   + Show previous and current text- Hide previous and current text

   Previously

   Deployed active-duty military against civilian populations in a U.S. city without Insurrection Act authority, circumventing the constitutional framework requiring congressional authorization. The $134 million cost was borne by taxpayers. The ruling established that no president can use federalization of the National Guard to conduct domestic law enforcement in violation of the Posse Comitatus Act.

   Now

   Deployed active-duty military against civilian populations in a U.S. city without Insurrection Act authority, circumventing the constitutional framework requiring congressional authorization. The $134 million cost was borne by taxpayers. The ruling, which applies only to California and was appealed, found the administration had used federalized troops for law enforcement that the Posse Comitatus Act bars.

3. Sep 29, 2026UpdatedStatus

   On December 31, 2025, Trump announced he was withdrawing the National Guard from Los Angeles. The same day, the Ninth Circuit upheld a lower-court order directing that control of the troops be returned to Governor Newsom.[4]

   Previously

   blocked-by-court

   Now

   blocked-by-court (Posse Comitatus injunction Sept 2, 2025, appealed; Guard withdrawn from Los Angeles Dec 31, 2025)

4. Sep 29, 2026CorrectedSummary

   The entry called Judge Breyer's September 2, 2025 order the first-ever injunction against a Posse Comitatus Act violation. None of the cited sources says that, so 'first-ever' is removed. The title stated the deployment was unlawful as fact while the ruling is on appeal; it now says it was ruled unlawful.[3][2]

5. Sep 29, 2026ClarifiedSeverity rationale

   The severity rationale stated as fact that the deployment 'violated Posse Comitatus'; it now attributes that finding to the September 2, 2025 ruling. Severity unchanged.

   + Show previous and current text- Hide previous and current text

   Previously

   Deploying troops for domestic enforcement violated Posse Comitatus, a significant precedent but the deployment was blocked by court ruling.

   Now

   A federal judge found the use of troops for domestic enforcement violated the Posse Comitatus Act, a significant precedent, though the ruling was appealed, applies only in California, and blocked the activities.

6. Sep 29, 2026CorrectedCost estimate

   Updated to the Congressional Budget Office's January 2026 estimate that the Los Angeles deployment cost $193M through December 2025. The earlier $134M was the Pentagon's June 2025 projection for the first 60 days, and troops stayed longer. An unsourced ~$6M litigation add-on is removed, and a duplicate cost block for this event is removed so it is counted once.

   Previously

   net $134M so far; 10yr $140M; 15yr $140M

   Now

   net $193M so far; 10yr $193M; 15yr $193M

Sources [4]