What Research Says About Protests Against Military Deployments
President Donald Trump ordered 2,000 California National Guard troops into Los Angeles in June 2025—without consulting Governor Gavin Newsom—starting one of the biggest fights between federal and state government in recent American history. Within days, thousands of protesters flooded the streets, blocking highways and occupying federal buildings. The multi-week conflict that followed combined mass arrests, labor union mobilization, and a legal battle that reached federal court, where a judge would declare the entire deployment unconstitutional.
How a Workplace Raid Sparked a Constitutional Crisis
The deployment developed from expanded immigration enforcement operations by Immigration and Customs Enforcement throughout Southern California. Federal agents conducted a major workplace raid at Ambiance Apparel in downtown Los Angeles on June 6, 2025, arresting at least 45 people. Angry crowds gathered immediately at the site and mobilized across the broader Los Angeles area.
Trump’s response was swift and unilateral. The evening of June 7, White House Executive Associate Director Tom Homan announced on Fox News that National Guard troops would deploy to Los Angeles. That same evening, he signed a memorandum authorizing 2,000 California National Guard members to deploy under Joint Task Force 51 for 60 days or longer “at the discretion of the secretary of defense.”
Trump issued this order without obtaining consent from Governor Newsom, who legally controlled the California National Guard as state chief executive. The deployment represented a claim that federal law allows the president to take control of state troops—but without the legal authority courts said he needed.
Within days, the federal military presence expanded. On June 9, he authorized deployment of an additional 2,000 Guard members. The Pentagon sent 700 Marines, who arrived in greater Los Angeles on June 10. By that date, 2,100 federalized Guard members were on city streets. Photographs showed them accompanying and protecting ICE agents during immigration arrests—a law enforcement role that would form the basis of legal challenges.
The Protest Movement Takes Shape
The response from immigrant rights advocates, labor organizers, and anti-enforcement activists was immediate. Large crowds numbering in the thousands gathered repeatedly at federal buildings and ICE facilities throughout the Los Angeles metropolitan area. Protesters came from a broad coalition: labor unions (particularly the Service Employees International Union), immigrant rights organizations, faith communities, and unaffiliated protesters responding to calls for action.
The tactical approach combined multiple strategies. Protesters occupied public space adjacent to federal buildings, blocking normal operations. Street-level demonstrations escalated to traffic disruption, with protesters blocking access to the Hollywood Freeway and surrounding thoroughfares during daytime hours. At Grand Park in downtown Los Angeles, police reported confronting approximately 30,000 protesters during an afternoon gathering, though the event ranged from peaceful assembly to instances where “some protesters hurled chunks of broken concrete toward officers.”
Police responded with tear gas and rubber bullets, hospitalizing at least one demonstrator with a head injury from rubber ammunition. The LAPD initiated a “citywide tactical alert” at 8:24 p.m., meaning police would use more organized and aggressive tactics across multiple precincts.
A Union President Gets Arrested
A pivotal moment occurred on June 6 when David Huerta, president of SEIU California, was arrested at the Ambiance Apparel raid location while attempting to document federal enforcement operations. According to the federal criminal complaint, Huerta arrived around noon and joined protesters in confronting federal agents carrying out a search warrant.
The complaint alleged that Huerta and others “seemed to be working together to disrupt the law enforcement operations,” with Huerta “yelling at and taunting officers” and later sitting “cross-legged in front of a vehicle gate.” When a white law enforcement van attempted to access the facility, Huerta stood in its path. Officers physically moved him and placed him under arrest.
The arrest of Huerta—a prominent labor leader—became a turning point that brought more people out to protest. Thousands of union members, activists, and supporters rallied for his release. Democratic Senators Adam Schiff and Alex Padilla sent a letter to the Homeland Security and Justice departments demanding a review of his arrest.
After several days in federal custody at the Metropolitan Detention Center, Huerta was released on June 9 on a $50,000 bond. He was initially charged with a felony count of conspiracy to impede an officer—carrying up to six years in federal prison—though prosecutors later reduced the charge to a misdemeanor of “obstruction resistance or opposition of a federal officer,” with a maximum sentence of one year.
The Legal Battle Unfolds
While street-level protests continued, state political leadership launched a separate lawsuit. Governor Newsom, who’d repeatedly characterized the Guard deployment as “purposefully inflammatory,” “reckless,” and “disrespectful to our troops,” filed an emergency lawsuit on June 9 in the U.S. District Court for the Northern District of California.
The state’s legal arguments centered on two claims. First, the state contended that Trump lacked legal authority under federal law (Title 10, section 12406) to federalize the Guard without following proper procedures. Those procedures would’ve required the deployment to be requested through the governor rather than unilaterally commanded by Trump. Second, the state argued that even if legal authority existed, the Tenth Amendment—which says powers not given to the federal government belong to states—prevented the federal government from taking over state military forces without gubernatorial consent.
U.S. District Judge Charles Breyer’s initial response was swift but mixed. On June 10, he denied the state’s request for an immediate temporary restraining order—a setback for the state’s position. But recognizing the gravity of the constitutional questions, Breyer agreed to temporarily stop the deployment on June 12, days after the lawsuit was filed.
In his June 12 order, Breyer ruled that Trump didn’t have legal authority to deploy the Guard and was violating the Tenth Amendment. The judge’s order blocked the federal deployment and restored control of the Guard to Governor Newsom until more court hearings.
The Appeals Process
The administration immediately appealed to the Ninth Circuit, filed opposition characterizing the state’s lawsuit as a “crass political stunt,” and argued that Trump’s decision wasn’t reviewable by the courts. Before Breyer’s ruling took effect on June 12, the Ninth Circuit put the judge’s order on hold and scheduled a hearing for June 17. This legal move—putting the judge’s order on hold while they appealed—allowed the military deployment to continue while the legal challenge proceeded.
The case continued to unfold over months. During this extended legal battle, Guard units remained federalized and continued operating under federal command. Their personnel served law enforcement functions that critics—including former four-star admirals and generals who filed legal arguments supporting California’s case—argued violated the Posse Comitatus Act, the federal statute that prohibits use of the military for domestic law enforcement.
After months of legal fighting and a three-day trial, Judge Breyer issued a major ruling on September 2, 2025. He found that the administration had violated the Posse Comitatus Act and ordered the administration not to use Guard or military troops for civilian law enforcement in the state. Breyer’s written opinion stated that there was “no rebellion, nor was civilian law enforcement unable to respond to the protests and enforce the law.” The judge found the administration’s rationale for deployment to be “contrived”—manufactured to provide justification for a desired military deployment.
The government appealed Breyer’s September 2 ruling on September 3. The Ninth Circuit temporarily put the order on hold on September 4, once again allowing the deployment to continue while the appeal was being decided. In December 2025, after months of legal maneuvering, Judge Breyer ordered Trump to cease the Guard deployment in Los Angeles. The Ninth Circuit upheld this order on December 12, directing the federalized Guard troops to leave the city by noon on December 15.
Following these judicial defeats, Trump ended the National Guard deployment in Los Angeles on December 31, 2025—approximately seven months after initially issuing the deployment memorandum.
Who Organized the Movement
Protesters represented a mix of different groups, ranging from established labor unions with significant financial and communications resources to grassroots immigrant rights networks and faith-based organizations.
The most visible institutional force was organized labor, particularly the Service Employees International Union, which represents approximately 700,000 home care workers across the United States, including over 100,000 in the state alone. The SEIU, founded in 1921 as the Building Service Employees Union, has a long organizational history of representing immigrant and low-wage workers, including immigrants without legal status.
Immigrant rights groups included organizations with deep roots in Los Angeles’s immigrant communities. The Coalition for Humane Immigrant Rights of Los Angeles (CHIRLA), founded in 1986 as a response to the Immigration Reform and Control Act, has served as a main organization for immigrant advocacy and organizing in Los Angeles for nearly four decades. CHIRLA works on education, political advocacy, community organization, deportation defense, and workers’ rights.
Beyond established organizations, protesters drew on existing networks and relationships—the communication tools and connections that enable rapid mobilization when something sparks action. The immediate response in June 2025 suggests that such networks existed in Los Angeles, having been developed over years of immigration enforcement conflicts and previous protest mobilizations against ICE enforcement.
What Research Says About These Tactics
Political scientist Erica Chenoweth’s landmark study analyzing 323 nonviolent and violent campaigns from 1900 to 2006 found that nonviolent campaigns succeeded approximately 53 percent of the time in achieving major goals (like changing the government), compared to only 26 percent success rate for violent insurgencies. Chenoweth’s research indicates that nonviolent movements succeed because they attract broader participation, make it easier for people to join, and make it easier for military and police forces to defect or refuse violent orders.
By this research standard, the 2025 Los Angeles protests—which remained predominantly nonviolent despite some property damage and minor confrontations—aligned with strategies most likely to work.
Research also indicates that success depends on scale and duration. Chenoweth’s “3.5 percent rule” suggests that when roughly 3.5 percent of a population mobilizes in active, nonviolent resistance, it can force political change. The Los Angeles protests, which drew thousands of protesters across multiple weeks, likely represented a meaningful percentage of Los Angeles’s population and reached this level of ongoing protests needed to have political power.
The Disruption Dilemma
Research on disruptive protest tactics—such as highway blockades and federal building occupations—presents mixed findings regarding public opinion impact. Studies have found that disruptive tactics decrease public support for protesters and protest groups, even while increasing media attention and how much attention the issue gets.
This research suggests that while disruption generates visibility, it may alienate portions of the public whose support or at least neutrality is necessary for long-term success. Some research indicates that when disruption includes property damage or appears violent, public support can decline by 12 percentage points or more.
The implication for the 2025 Los Angeles protests is that while the disruption tactics (highway blockades, federal building occupation) likely attracted media attention and raised visibility of federal overreach, these same tactics may have alienated some portion of Los Angeles residents whose support would’ve strengthened the political position.
Did the Protests Work?
The most concrete measure of success would be whether protests prevented or reversed the Guard deployment—the stated primary demand. Looking at it this way, the street-level protests alone didn’t achieve this objective. Despite weeks of continuous protests, the Guard remained deployed until December 31, 2025, approximately seven months after Trump initially ordered the deployment.
But this view might miss the impact. The protests occurred in a complex institutional and legal environment where multiple actors pursued different strategies with overlapping effects. While street protests didn’t independently reverse the deployment, they coincided with and likely created political space for Governor Newsom’s aggressive legal challenge.
The combination of public protest pressure and gubernatorial legal action proved more effective than either would’ve been independently. In September 2025, Judge Breyer’s ruling that the deployment violated the Posse Comitatus Act—a ruling that emerged from months of legal work that began immediately after the protests started—found in favor of the state’s legal position. By year’s end, the deployment had ended.
Did the street protests cause the deployment’s reversal, or did the legal challenge achieve this outcome? In social movement analysis, it’s rarely possible to draw a straight line from one thing to another. Multiple strategies operating simultaneously created combined pressure that changed what happened.
The street protests made the issue visible and made the deployment look wrong through visible public opposition. The legal challenge provided constitutional arguments for why the deployment was unlawful. Federal courts sided with the state on the law, in part because the claim that there was genuine public safety emergency requiring military deployment appeared false—as evidenced by the protests that law enforcement could contain without military assistance.
Historical Context
Similar confrontations between state and federal authority, similar military deployments, and similar protest responses have occurred multiple times across American history.
The most parallel historical example involves the federal militarization of Little Rock, Arkansas in 1957 to enforce school desegregation. President Dwight Eisenhower federalized the Arkansas Guard and deployed federal troops to Little Rock to enforce a federal court order desegregating schools, overriding the opposition of Arkansas Governor Orval Faubus. Though the context differed—Little Rock involved military enforcement of federal authority in support of protesters’ rights, rather than suppression of protests—the question of whether federal or state government has power over military forces remained comparable.
More relevant are instances where federal forces suppressed protest movements. The Kent State shootings of May 4, 1970, represent an extreme case of military response to student anti-war protests, where Ohio Guard troops fired into a crowd of students, killing four and wounding nine. Though not a federal deployment for protest suppression (the guard was called by state authorities), the incident demonstrates the catastrophic risks when military forces confront civilian protesters.
The shootings transformed the political environment around the Vietnam War, generating massive additional protests and strengthening anti-war sentiment. The tragedy prompted the President’s Commission on Campus Unrest to conclude that “The indiscriminate firing of rifles into a crowd of students and the deaths that followed were unnecessary, unwarranted, and inexcusable.”
These historical parallels suggest that military deployments against protesters, particularly when perceived as excessive or unjustified, tend to make the government action look wrong and strengthen protest movements rather than suppress them. The visibility and drama of military presence becomes evidence of government overreach, potentially expanding rather than contracting support.
The 2006 Immigration Protests
The Great American Boycott of May 1, 2006, represented one of the largest protest mobilizations in modern American history, with an estimated 1.25 to 1.5 million participants across multiple cities, including over 500,000 to 1.3 million in Los Angeles alone. These immigration protests were organized in response to proposed federal legislation (HR 4437) that would’ve criminalized illegal immigration and made assisting immigrants a felony.
The massive scale of the 2006 protests made immigration a central political issue and helped mobilize Latino voter participation, yet the protested legislation failed in Congress despite the federal government’s desire to pass it. The lesson here is that massive, visible protests can influence legislative outcomes, though not in straightforward or obvious ways.
More recent immigration enforcement protest history includes the Occupy ICE Portland movement of June 2018, where protesters established a 38-day encampment at the ICE Portland field office, physically blockading the facility and preventing normal operations. The Portland encampment demonstrated that the strategy of blocking the building for a long time could disrupt law enforcement operations and attracted support, with hundreds of people at peak participation.
The encampment dispersed when law enforcement threatened federal charges against organizers, but the strategy of blocking the building for a long time proved effective at preventing operations. The 2025 Los Angeles protests borrowed from this Occupy ICE Portland precedent, trying to disrupt operations the same way through occupation and blocking of federal facilities.
Strategic Lessons
The conflict demonstrates that street-level mass protest, when combined with legal strategy, can challenge federal power grabs. Judge Breyer’s ruling that the deployment violated the Posse Comitatus Act and the Tenth Amendment likely wouldn’t have been reached without the political pressure that pushed judges to act through visible public opposition through protests. Conversely, the legal strategy alone, pursued by the state’s attorney general without public mobilization, might’ve lacked the political pressure necessary for judicial intervention.
The tactical choices—highway blockades, federal building occupation, sustained encampments, strategic arrest of prominent leaders—matched what’s worked in the past. Labor unions joining with immigrant rights activists is a change that strengthens both movements. The visibility of David Huerta’s arrest and detention, rather than silencing a critic, helped raise awareness and increase political power.
But the conflict also shows the complicated relationship between disruptive tactics and public opinion. Research indicates that blocking highways and aggressive confrontations with police decrease support for protesters among certain publics, even while generating media attention. The 2025 protests’ success appears to have depended not on disruption alone but on the combination of disruption, labor institutional power, legal challenge, and judges who agreed there were constitutional limits on federal power.
What Comes Next
As of the conclusion of the Guard deployment in late December 2025, protesters face questions about whether it can keep going and how it might change. The immediate fight between federal and state government that sparked protests has technically resolved through the courts, yet the broader context that sparked the protests—intensive ICE enforcement operations, immigrant community vulnerability, labor willingness to mobilize—remains unchanged.
Protesters could maintain momentum by shifting focus to other targets and tactics. The ending of the Guard deployment doesn’t mean the political conflict is resolved. ICE operations continue, and the administration has prioritized immigration enforcement as an objective.
Organizers could turn street protests into election work as the 2026 midterm elections approach. The demonstrated ability to mobilize thousands around immigration issues, combined with labor union components, positions them to influence electoral outcomes in the state. Democratic candidates dependent on labor and immigrant community support would need to take positions responsive to demands, creating leverage over both primary elections and general election outcomes.
Alternatively, protesters could lose steam and people could stop showing up—a common pattern after initial crisis moments pass. The immediate crisis that sparked mobilization has resolved through court action. Without ongoing triggering events, movements often see participation decline as people get busy with other things.
For future movements challenging military deployments or federal overreach, the lessons appear to be these: sustained, visible, mass mobilization creates political pressure necessary to support legal challenges. Institutional backing from established organizations like labor unions amplifies power beyond what grassroots activism alone achieves. Combined protest and legal strategy makes both stronger than either would be alone. Dramatic confrontations that result in arrest of prominent figures can strengthen rather than weaken movements if handled strategically for political messaging. And federal overreach that appears to violate constitutional principles finds vulnerable ground in courts, particularly when supported by political pressure from affected communities.
As immigration enforcement and federal-state conflicts likely continue in the years following this event, the 2025 Los Angeles protests will serve as a template and precedent for subsequent resistance efforts. Protesters demonstrated that Guard deployment against protesters doesn’t look right to the public, that courts will intervene to check such deployment when properly challenged, and that coordinated labor-immigrant rights mobilization has political power. These lessons, based on past examples and learned through the lived experience of thousands of activists, represent the accumulated knowledge of how contemporary movements can challenge military deployment and federal overreach through combined protest and legal strategy.
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