A person in local police custody cannot be further detained through an immigration detainer from ICE (U.S. Immigration and Customs Enforcement), per a new federal court case,Jimenez Moreno et al v. Napolitano.
An immigration detainer is a request that local police detain a person (up to 48 hours) after the person is otherwise eligible for release, in order for ICE to take the person into federal custody. In terms of public safety, one effect of this confusion between local law enforcement and immigration enforcement is that immigrants may have feared reporting a crime could lead to deportation.
In the Jimenez Moreno case, the issue was whether ICE overstepped its authority by issuing immigration detainers without first obtaining arrest warrants.
The court found that although ICE may detain a person believed to be a removable foreign national, such detainer is subject to the constitutional threshold for arrest, i.e. a warrant issued with probable cause (except if the suspect is likely to escape before a warrant can issue). As a result, immigration detainers issued against the plaintiffs in the case are void; however, the legal reasoning in this case could apply to countless other detainers issued by ICE. Practically speaking, ICE can still detain a person but must go through the process of obtaining a warrant first.