How has the Insurrection Act been used or threatened by U.S. presidents in the 20th and 21st centuries?

1. Presidential deployments to enforce civil‑rights and federal law

Mid‑20th century presidents relied on the Act to enforce federal court orders and protect Black Americans from violent local resistance: Dwight D. Eisenhower sent federal troops to Little Rock to escort school desegregation, and Presidents Kennedy and Lyndon B. Johnson invoked the statute in multiple desegregation crises to ensure federal orders were carried out ^[1][4][5]. Those uses reflect the Act’s constitutional role as a backstop when state authorities refuse or fail to protect constitutional rights, a reading embedded in later statutory amendments that permit federal intervention when “a class of people is deprived” of protections ^[5][6].

2. Industrial unrest, riots and other 20th‑century invocations

Beyond civil‑rights enforcement, the Act was called in during violent labor and civil disturbances in the 20th century—President Woodrow Wilson sent troops to Colorado amid deadly strikes in 1914, and other 20th‑century presidents used the law in response to large riots and breakdowns of public order—most recently in the late 20th century—showing the statute’s use as an emergency tool when local forces are overwhelmed ^[7][1][8].

3. The 1992 Los Angeles riots and the last major use

The most recent widely cited invocation came during the 1992 Los Angeles riots, which the record and summaries list as the last major deployment under the Insurrection Act; contemporary compendia note roughly 30 invocations across U.S. history, with that Los Angeles action marking the last time federal troops were broadly used under the statute ^[9][2][3].

4. From invocation to threat: 21st‑century presidential posturing

In the 21st century presidents have more often threatened the Act than exercised it; former President Donald Trump repeatedly floated invoking the statute to deploy troops to American cities—most notably signaling the possibility for Minneapolis and other unrest sites—while also sending federal officers and troops under other authorities, a practice that drew scrutiny because it blended real deployments with public threats and occasional factual errors about the law’s history ^[2][7][6]. Reporting documents that Trump has publicly “mused” about the Act and has inaccurately claimed statistical histories of its invocation, illustrating how threats can be used as a political lever even when legal constraints make actual use complicated ^[2].

5. Legal vagueness, presidential discretion, and partisan debate

Legal scholars and advocacy groups highlight that the Insurrection Act’s broad, sparsely defined standards give presidents wide latitude to decide when domestic military deployment is “necessary,” a concern emphasized by the Brennan Center and other researchers who argue the statute is an unusually potent emergency power with insufficient guardrails in the modern era ^[1][3]. Critics warn this latitude risks military involvement in political policing; proponents and historical actors argue the statute is a vital, narrowly tailored remedy when states will not enforce constitutional rights or public order ^[1][3].

6. Patterns and limits: rare use, outsized consequence

The pattern across the 20th and 21st centuries is clear: the Insurrection Act is rare in practice but consequential in impact—used decisively in the civil‑rights period and in major riots or strikes, and more recently invoked rhetorically as part of executive strategy—while historians and legal analysts note its scarcity since the 1960s and emphasize the need to weigh the Act’s historical role against modern democratic and legal norms ^[8][3][9].