How does ICE authority intersect with local police authority in immigration enforcement?
Executive summary
ICE’s delegated authority intersects with local police mainly through the 287(g) program, which lets ICE train and authorize state and local officers to perform specific immigration-officer functions under ICE supervision [1]. That delegation has surged in 2025 — ICE reports 1,190 287(g) agreements nationwide as of Nov. 25, 2025 — and activists, some lawmakers and courts have pushed back, citing community trust, racial‑profiling risks, and legal limits on warrantless arrests [1] [2] [3] [4].
1. How delegation actually works: federal authority under a local badge
The statutory mechanism is Section 287(g) of the Immigration and Nationality Act, which allows ICE to “delegate” specified immigration‑officer functions to state and local law enforcement under written memoranda of agreement; those delegated duties are supposed to be performed “under the agency’s direction and oversight,” meaning local officers act with limited federal immigration authority only after ICE training and certification [1]. ICE’s public materials describe three models — jail enforcement, warrant service, and a task‑force model — each with different scopes for where and how local officers can exercise immigration powers [1].
2. Recent scale-up and what that changes on the ground
In 2025 ICE dramatically expanded 287(g) partnerships; ICE’s tally shows hundreds more MOAs, and reporting highlights rapid growth in some states where local agencies “exploded” into agreements after the program’s revival [1] [5] [2]. That expansion translates into more local officers being “deputized for limited immigration enforcement,” enabling them to question, detain or process people for immigration violations in contexts that previously were mostly federal [3] [2].
3. Models matter: where local officers can use immigration powers
The different 287(g) models constrain location and activity: jail models largely operate inside detention facilities or during processing of arrested people; the Task Force Model explicitly authorizes some immigration enforcement during routine police duties as a “force multiplier,” while the Warrant Service Officer model focuses on serving administrative warrants [1] [5]. How an agency signs on determines whether officers can act on the street, at traffic stops, or mainly in jails [1] [5].
4. Legal and policy frictions: state, local and judicial limits
Local and state officials don’t have unfettered power to perform federal immigration functions: state laws and attorney general guidance can limit local cooperation (for example, Maryland’s AG guidance telling officers not to perform “the functions of an immigration officer”), and courts have constrained some ICE tactics — a federal judge in Colorado ordered limits on warrantless arrests by immigration officers in that district [6] [4]. Those measures show competing authorities: federal delegation via 287(g) versus state/local policies and judicial oversight [1] [4] [6].
5. Community trust and policing tradeoffs
Elected officials and advocates in multiple places warn that deputizing local cops for immigration work can erode trust between police and immigrant communities, potentially deterring crime reporting and cooperation; state lawmakers and local residents have voiced those concerns when 287(g) mandates or policies were proposed [3] [7] [8]. Conversely, proponents — including some state legislators and DHS/ICE statements — argue the partnerships bring federal resources and help remove criminal noncitizens, framing 287(g) as a public‑safety tool [3] [9].
6. Real‑world controversies and accountability gaps
Reporting shows concrete incidents and legal scrutiny: some jurisdictions face community pushback and policy revisions after local measures appeared to permit police to assist ICE without warrants, and courts have pushed back on warrantless arrest practices that ICE used to expand detentions [8] [4]. Advocates cite risks of racial profiling and insufficient oversight; officials supporting 287(g) emphasize oversight is built into ICE’s direction and that the program targets criminal aliens [1] [3] [2].
7. Practical implication for everyday interactions
If a local agency participates in a 287(g) agreement — especially a Task Force Model — officers may have the authority to question immigration status, detain people for ICE, or process immigration violations during routine enforcement actions, whereas in non‑participating jurisdictions those immigration functions generally remain federal [1] [5] [2]. Whether that authority is exercised, limited by local policy, or checked by courts depends on the specific MOA, state/local rules, and recent judicial decisions [1] [6] [4].
Limitations and open questions
Available sources document the statutory mechanism, the growth of 287(g) in 2025, examples of local debate, and judicial pushback, but they do not provide a comprehensive, empirical comparison of outcomes (e.g., measured effects on crime reporting, racial‑profiling statistics, or removal rates across every jurisdiction) — those specific data points are not found in current reporting (not found in current reporting).