What legal reasons lead ICE to arrest U.S. citizens and how often are those cases misidentifications?

1. Why ICE says it sometimes takes citizens into custody — the agency’s legal posture

ICE and DHS maintain that enforcement operations target noncitizens and that agents are trained to verify status before taking action; DHS publicly insisted its operations “are not resulting in the arrest of U.S. citizens” and that encounters with citizens reflect lawful arrests for criminal conduct or isolated incidents ^[4]. Agency dashboards also show ICE’s Enforcement and Removal Operations is authorized to execute arrests and detain people it believes are removable, and it reports large volumes of arrests broken down by country of citizenship and criminal history ^[5]. Available reporting does not indicate ICE claims a general legal right to deport citizens; instead, when citizens are arrested DHS frames those as mistakes or as arrests for non‑immigration offenses ^{[4] [5]}.

2. What independent reviews and reporting identify as actual causes

Multiple outside investigations and legal practitioners identify recurring technical and procedural causes: database mismatches, “biographical collisions” (people who share names or birthdates), outdated records, and algorithmic false positives used in screening and targeting ^{[2] [1]}. The Government Accountability Office (GAO) found ICE and CBP guidance on citizenship investigations is inconsistent and that the agencies do not systematically track these encounters, and cited internal ICE data indicating arrests, detentions and removals of some U.S. citizens ^[1]. Advocacy organizations and news outlets documented hundreds of cases over recent years where citizens were detained or even removed before citizenship was recognized ^{[3] [2]}.

3. How often this happens — numbers, limits, and why totals vary

Available sources show different slices of the problem but converge on “hundreds” rather than thousands. GAO reported ICE data indicating 674 arrests, 121 detentions and 70 removals of potential U.S. citizens in its data sample ^[1]. ProPublica and other investigations cited in reporting compiled evidence of “170+” citizens detained in certain investigative windows and broader counts of hundreds across longer periods ^{[2] [6]}. The American Immigration Council warned the true number could be higher because ICE and CBP do not maintain adequate records to determine the full scope ^[3]. In short: documented incidents number in the low hundreds, but incomplete agency tracking means the total is uncertain ^{[1] [3]}.

4. Collateral effects of aggressive enforcement operations

Recent, intensified operations that arrest many people per day create more opportunities for error. Reporting shows ICE’s ERO unit was arresting roughly 1,100 people per day during recent spikes, and advocates say broader mandates encouraging “collateral arrests” increase the risk of detaining bystanders or household members who turn out to be citizens ^[7]. Local reporting from scenes such as New Orleans documents multiple instances where people who identified themselves as U.S. citizens were nevertheless detained and later released after proving status, underlining how fast, public operations can sweep up citizens ^[8].

5. Competing narratives and political context

There is a sharp split in framing. Watchdogs, members of Congress and civil‑rights groups describe systemic failures and rising frequency under aggressive enforcement policies and demand investigations and reforms ^{[9] [6]}. DHS disputes those characterizations, calling some media accounts “false reporting” and insisting citizens are not being deported and that agents perform due diligence ^[4]. Both sides cite internal data or selective incidents; the key factual tension is that agency record‑keeping is incomplete and external analyses document multiple confirmed mistakes ^{[1] [3]}.

6. What the sources do and do not say — limits for the reader

Sources document patterns (database errors, biographical collisions) and give concrete ICE figures for “potential U.S. citizens” and dozens to hundreds of confirmed incidents, but they also flag gaps: ICE and CBP do not systematically track citizenship investigations, so available counts likely underreport the full scope ^{[1] [3]}. Sources do not provide a definitive, comprehensive national tally or standardized error rate across all operations; they instead offer partial datasets, case studies and watchdog counts that point to a persistent problem ^{[1] [2] [3]}.

Bottom line: ICE’s public stance is that it targets noncitizens and does not deport citizens ^[4], but independent reporting, GAO analysis and advocacy groups show repeated, documented incidents caused by data and procedural failures that have resulted in hundreds of wrongful arrests or detentions — a problem made harder to quantify because ICE and CBP do not consistently track these cases ^{[1] [2] [3]}.