Despite the notion that everyone should have their “day in court,” the mass processing of evictions, consumer debt cases, foreclosures, and certain immigration cases depends on widespread acquiescence. Most people subject to these legal cases do not mount a vigorous legal defense—and often default entirely—despite the significant stakes involved. But what if everyone fought back? Activists and lawyers have long dreamed of “flooding” unjust court systems to stymie their operation and force them to change.

This Article takes flooding the courts from theory to practice: it examines three case studies where advocates sought to defend claims en masse, with a goal of instigating reform through inundating opposing parties and the courts. In San Francisco in the early 2000s, advocates represented thousands of unhoused people in traffic court to challenge the police citations they received for activities linked to their homeless status. That campaign and related advocacy efforts eventually led the city to agree to a deal to dismiss citations where unhoused people accessed social services—and ultimately to stop issuing arrest warrants for unpaid citations. In Boston, during the Great Recession, advocates sought to represent every tenant facing post-foreclosure eviction in housing court, alongside engaging in political advocacy and protests. The combined effort allowed many residents to stay in their homes or to buy back foreclosed homes on more affordable terms than their original mortgage. In Washington, D.C., an effort by Democratic Socialists to flood housing court failed, ultimately leading organizers to pivot to other strategies. Even though more tenants showed up to court after organizers canvassed neighborhoods to urge people to contest their evictions, they did not do so at sufficient scale to change the behavior of landlords or the court.

Drawing on interviews, first-hand accounts, and other evidence, I argue that successful efforts to flood the courts overcame serious challenges: 1) identifying and mobilizing vast numbers of affected individuals; 2) providing legal aid at exceptional scale without a right to counsel; 3) ensuring that the benefits of participation in such a strategy outweighed the risks for vulnerable people; and 4) pursuing goals that were concrete and realizable within particular political environments. Flooding the courts did not succeed in isolation—as a romanticized dream of disrupting unjust systems through legal contestation alone—but only as part of broader political strategies devised by organizers with deep roots in the affected communities.