An immigration detainer is a written request from U.S. Immigration and Customs Enforcement (ICE) asking a local jail or other law enforcement agency to hold a person for up to 48 additional hours after they would otherwise be released, so that ICE can take them into federal custody for possible deportation. It is issued on Form I-247A by an ICE officer, not a judge. It is a civil immigration tool, not a criminal warrant, and local agencies are not legally required to comply with it.
How a Detainer Gets Issued
Detainers start with a routine booking. When someone is arrested and booked into a jail, their fingerprints go to the FBI for a criminal background check. Under a federal information-sharing arrangement, those prints are also forwarded to Department of Homeland Security immigration databases.1U.S. Immigration and Customs Enforcement (ICE). Archived: Secure Communities If the check flags the person as a non-citizen who may be deportable, has a prior removal order, or is otherwise potentially removable, an ICE officer decides whether to issue a detainer and sends it to the jail electronically or by fax.
No judge reviews this decision. It is made by an ICE officer looking at federal databases.
What the Detainer Asks the Jail to Do
Form I-247A makes two specific requests of the jail.2Department of Homeland Security. Immigration Detainer – Notice of Action First, notify ICE before the person is released for any reason. Second, keep holding the person for up to 48 hours beyond their normal release time so ICE agents can arrive and take custody.
The detainer does not begin deportation proceedings on its own. It exists to bridge the gap between criminal custody and federal immigration custody so the person does not walk out the door before ICE arrives.
For the detainer to take effect against the person, the jail is supposed to serve them with a copy of the form. The form itself has a space where the jail documents when and how it delivered that notice.
The 48-Hour Clock
The 48-hour window is the part that matters most in practice. Under 8 CFR 287.7(d), the clock starts when the person “would otherwise be released” from criminal custody.3eCFR. 8 CFR 287.7 – Detainer Provisions Under Section 287(d)(3) That usually means the moment bail is posted, a sentence is finished, charges are dropped, or the person is otherwise cleared on the criminal side.
There is a real inconsistency about weekends and holidays. The regulation still contains language excluding Saturdays, Sundays, and federal holidays from the 48-hour count, which could stretch a Friday-evening hold into Monday or Tuesday. The current Form I-247A, however, dropped that exclusion and requests a flat 48 hours. Which one applies in practice depends on the jail.
If ICE does not arrive within the 48 hours, the jail is required to release the person. ICE’s own guidance states the agency may not lawfully hold anyone beyond that period.4U.S. Immigration and Customs Enforcement. Immigration Detainers
A Detainer Is Not a Warrant
This distinction is central. A criminal warrant is issued by a judge who has reviewed evidence and found probable cause. It legally compels action. An ICE detainer is issued by an immigration officer who believes the person is deportable under civil law. There is no judicial review.
Because the detainer is a request, local jails and sheriffs are not required to honor it. The Third Circuit held in Galarza v. Szalczyk that the federal detainer regulation “merely authorizes the issuance of detainers as requests to local LEAs” and does not compel compliance.5Justia Law. Galarza v Szalczyk, No. 12-3991 (3d Cir. 2014) Other federal courts have found that when a jail voluntarily holds someone past their release date solely because ICE asked, that hold is a new Fourth Amendment seizure. Without a judicial warrant, the jail itself can be sued for unlawful detention.
Detainers often arrive alongside an administrative warrant. Form I-200 is a Warrant for Arrest of Alien. Form I-205 is a Warrant of Removal/Deportation. Despite the name, neither is signed by a judge or neutral magistrate. Both are issued internally by ICE and directed at federal immigration officers. Neither satisfies the constitutional warrant standard.
Whether the Jail Will Honor It
Because compliance is voluntary, responses vary sharply between jurisdictions. Some jails fully cooperate: they notify ICE of upcoming releases and hold people for the full 48 hours. Other jurisdictions, often called “sanctuary” jurisdictions, limit or prohibit their jails from honoring detainers. Some sanctuary policies permit notifying ICE but forbid the extended hold. Others prohibit both.
For someone with a detainer lodged against them, the practical outcome depends on which county or city holds them. There is no single national answer.
How a Detainer Affects Bail and the Criminal Case
An active detainer can create a difficult bind. Prosecutors and judges sometimes point to the detainer as a reason to set higher bail or deny release, arguing that ICE will take the person into custody anyway and that they may not be available for future court dates.
Even when bail is set and paid, a detainer means the person does not walk free. Posting the bond satisfies the criminal hold, but the 48-hour ICE window then begins. Anyone paying bail or a bondsman needs to understand this. Posting bail with an active detainer does not produce immediate release. The jail will keep the person for up to another 48 hours while waiting for ICE.
Detainers can also cut against eligibility for pretrial diversion and other alternatives to incarceration, since prosecutors and judges may doubt the person will be around to complete the program.
Rights of the Person Named in a Detainer
People held on immigration detainers have several protections on paper. Enforcing them from inside a jail is harder than reading them.
- You have the right to receive a copy of the detainer. The jail must serve you with Form I-247A for the detainer to take effect. If you have not been given one, ask jail staff directly.
- You have the right to an attorney, but not a free one. Federal law gives you the right to counsel in removal proceedings at no expense to the government. Unlike criminal cases, there is no constitutional right to an appointed immigration lawyer. You have to hire one or find legal aid.6Office of the Law Revision Counsel. 8 USC 1362 – Right to Counsel
- You have the right to be released if ICE does not arrive within 48 hours. The jail cannot lawfully hold you beyond that.
- You can challenge the detention. If the hold exceeds 48 hours or lacks legal basis, you can petition for a writ of habeas corpus, which forces the government to justify continued detention before a judge.
If you or a family member has a detainer, contacting an immigration attorney early makes a real difference. Many decisions that shape the outcome need to happen before the transfer to ICE, and they get harder afterward.
What Happens If ICE Takes Custody
Once ICE arrives, the person enters the federal immigration detention system. ICE policy requires that before transport, the person be told in a language they understand that they are being moved to another facility, not being deported at that moment. ICE must also provide the receiving facility’s name, address, and phone number in writing, and the person is entitled to a free phone call on arrival.7U.S. Immigration and Customs Enforcement. Policy 11022.1: Detainee Transfers
What follows depends on immigration history and criminal record. Some people can request a bond hearing before an immigration judge and argue for release while their case moves forward. Immigration bonds must be paid in full, with a minimum of $1,500 and amounts often much higher. Others face mandatory detention with no bond option, especially those with certain criminal convictions or who entered without inspection.
ICE can transfer detainees to any facility in the country, sometimes hundreds or thousands of miles from family, counsel, and the jurisdiction where a criminal case is still open. Detained immigration cases also move faster than non-detained ones, which puts pressure on someone trying to arrange representation from a remote facility.
Family trying to locate someone after transfer can use the ICE Online Detainee Locator System, which needs either the person’s name, country of birth, and date of birth, or their 8- or 9-digit A-number. If the system does not return results, the next step is contacting an ICE Enforcement and Removal Operations field office.8USAGov. Locate Someone Being Detained by ICE for Immigration Violation
If the Hold Goes Past 48 Hours
When a jail holds someone beyond 48 hours, or detains them based solely on a detainer without independent legal authority, there may be grounds for a civil rights claim. Federal courts have repeatedly found that holding a person past their release date on nothing more than an ICE request can violate the Fourth Amendment.
The legal exposure falls on the jail, not on ICE. No federal statute shields local agencies from lawsuits arising from detainer holds, and ICE has not offered to indemnify local officials who comply. That risk is one reason many jurisdictions have moved away from honoring detainers.
For someone currently held past the 48-hour mark, the most direct tool is a habeas corpus petition asking a court to order the government to justify the detention. An immigration attorney or civil rights organization can often file one on an emergency basis. The earlier it is filed, the sooner a judge reviews whether the hold has any legal basis at all.