ICE Detainer & Sanctuary Cities: What to Know

An ICE detainer is a voluntary request — not a court order — asking a local jail to hold a person up to 48 extra hours so ICE can arrange an arrest. Sanctuary cities limit cooperation with such requests, meaning local officers will generally not hold you beyond your release date. If ICE wants to detain you, it must typically do so independently. Verify current local policies with official city or county sources.

What Is an ICE Detainer?

An ICE detainer (officially Form I-247A) is a written request issued by U.S. Immigration and Customs Enforcement to a state or local law enforcement agency. It asks that agency to notify ICE before releasing a person from custody and to hold that person for up to 48 additional hours (excluding weekends and holidays) so ICE agents can take custody.

Key legal point: federal courts have repeatedly found that ICE detainers are civil requests, not mandatory orders. Local jurisdictions are under no constitutional obligation to honor them. For the full text of immigration enforcement authority, see ICE's official website.

Immigration attorney Ilya Fishkin, immigration attorney advises clients to understand the difference between a detainer and an actual judicial warrant before taking any action.

How Sanctuary Cities Respond to ICE Detainers

The term "sanctuary city" has no single legal definition, but it generally refers to a jurisdiction that limits its cooperation with federal immigration enforcement through local ordinances or policies. Common sanctuary practices include:

• Refusing to honor detainer requests absent a judicial warrant signed by a judge
• Not sharing release dates or personal information with ICE unless required by federal law
• Prohibiting local officers from asking about immigration status during routine encounters
• Releasing individuals as soon as their criminal case concludes, without extra holds

Sanctuary policies do not prevent ICE from making arrests independently on public streets or at courthouses. They only restrict how much local government resources and cooperation ICE receives.

Steps to Take If an ICE Detainer Is Filed Against You

1. Do not sign anything voluntarily without speaking to an immigration attorney first. Signing certain documents can waive your rights or agree to voluntary departure.
2. Request a copy of the detainer (I-247A) from the facility. You have the right to see the document.
3. Ask whether a judicial warrant exists. A detainer alone is not a judicial arrest warrant. Demand to see a warrant signed by a judge if the facility claims it must hold you.
4. Contact an immigration attorney immediately. Time is critical — the detainer hold window is 48 hours (excluding weekends and holidays).
5. Notify family or a trusted contact so they can assist in finding legal representation.
6. If released, follow all conditions of any supervision or check-in requirements and attend all immigration court hearings to avoid a deportation order in absentia.

What the Law Says

ICE detainer authority derives from 8 C.F.R. § 287.7, which authorizes ICE to issue detainers but does not compel local compliance. Federal circuit courts — including the Ninth and Fourth Circuits — have held that mandatory detainer enforcement without probable cause and a judicial warrant can violate the Fourth Amendment of the U.S. Constitution.

Under INA § 236, ICE has broad authority to arrest and detain noncitizens, but this authority belongs to federal agents, not local officers acting without independent authority. If removal proceedings are initiated, you have the right to a hearing before an immigration judge under INA § 240. Should you receive an order of removal, you generally have 30 days to file an appeal with the Board of Immigration Appeals (BIA), and 90 days to file a Motion to Reopen. For the most current information on fees and procedures, visit USCIS.gov.

This material is for informational purposes only and does not constitute legal advice