How does ICE define and classify detainees with criminal convictions versus civil immigration violations?
Executive summary
Immigration and Customs Enforcement (ICE) distinguishes detainees primarily by legal status and criminal history: it records people as having criminal convictions, pending criminal charges, or no convictions but civil immigration violations such as overstays or illegal entry (ICE’s own categories) [1]. In practice ICE’s public rules state that anyone who violates immigration law is eligible for arrest and detention while internal classifications and statistics reveal significant variation in who is detained and how “criminal” is defined and prioritized [2] [1] [3].
1. How ICE formally defines the categories
ICE’s operational reporting breaks detained people into three explicit buckets: individuals with criminal convictions, individuals with pending criminal charges, and individuals without convictions or charges who have broken U.S. immigration laws — the last category covering visa overstays, Visa Waiver Program violations and repeated immigration infractions [1]. ICE’s FAQ also emphasizes that all aliens who violate U.S. immigration law are subject to arrest and detention regardless of criminal history, signaling that civil immigration violations alone are sufficient grounds for ICE custody under agency policy [2].
2. What “criminal conviction” means inside ICE’s data systems
When ICE counts someone as a detainee “with a criminal conviction,” it typically records the person’s most serious recorded criminal conviction and assigns threat-level groupings for analysis; TRAC’s breakdown of ICE’s classification shows detailed listings of offense types and threat levels for those with convictions [4]. ICE and datasets compiled by academic projects preserve a person-level view tying arrests, detainers and detentions to underlying criminal-record fields, which allows reporting by most-serious conviction or by whether charges are pending [5] [1].
3. The legal difference between civil immigration violations and criminal offenses
Civil immigration violations — like unlawful presence, visa overstays, or administrative reentry violations — are not crimes under federal criminal statutes in many instances, but they are federal grounds for removal and for civil detention by ICE; ICE’s public guidance underscores that immigration law violations can prompt arrest and detention even absent a criminal record [2] [1]. Courts have constrained some local enforcement actions and imposed Fourth Amendment limits on arrests for immigration violations, but federal authority to detain for removability remains central to ICE practice [6].
4. The gap between ICE’s stated targeting and who is actually detained
Multiple independent analyses and news investigations report that a large share of people held in ICE custody have no criminal convictions: TRAC reported roughly 73.6% of ICE detainees had no criminal conviction as of late 2025, Cato and other researchers have found similar shares, and mainstream outlets documented thousands arrested without criminal records during recent interior operations [3] [7] [8]. At the same time, DHS and ICE release statements emphasizing arrests of the “worst of the worst,” including high-profile violent offenders, illustrating a competing public narrative focused on violent criminals [9] [10].
5. How priorities and language shape public perception
ICE’s FAQ frames enforcement as “prioritizing public safety” and locating “criminal aliens and immigration violators,” language that blurs the line between criminal and civil categories and supports a public framing focused on criminality even though agency data show many detainees lack criminal convictions [2] [1]. Critics and data analysts argue that selective use of “criminal alien” rhetoric obscures statistical realities — for instance, that the share of detainees with violent convictions has been low and declining in several reporting periods [11] [12].
6. What remains unclear or contested in reporting
ICE’s public materials define categories and assert broad arrest authority, while independent datasets—compiled by TRAC, academic projects and journalists—show trends in how many detained people actually have convictions; however, differences in coverage (e.g., ICE ERO actions only vs. Border Patrol) and timing make precise comparisons difficult and leave room for debate over how well internal classifications reflect enforcement priorities in the field [5] [1] [8]. Sources disagree in emphasis: DHS press releases highlight arrests of violent offenders [9], while data-focused outlets emphasize the rising share of civil immigration detentions and the low share of violent convictions [7] [11].