An immigration detainer is not a demand to a state law enforcement officer to make a civil arrest, but, if a state law enforcement officer acts on it, it is a new arrest. It is ripe for judicial review because, on the state’s mootness challenge, it is capable of repetition but evading review. It implicates the Fourth Amendment and the state constitution. Ramon v. Short, 2020 MT 69, 2020 Mont. LEXIS 876 (Mar. 25, 2020):
[*P23] This issue implicates both a fundamental constitutional right and concerns the legal power of a public official. Article II, Section 11, of the Montana Constitution, like the Fourth Amendment of the United States Constitution, prohibits unreasonable searches and seizures and aims to protect the privacy and security of individuals. Whether a state law enforcement officer can seize an individual and deprive that individual of his or her liberty based on a federal civil immigration detainer obviously presents a question of public importance that is relevant to both Montana law enforcement officers and residents.
[*P24] An answer will benefit Montana law enforcement officers by providing authoritative guidance on an unsettled issue regarding their authority to detain individuals, particularly given that there is no Montana Supreme Court ruling addressing this issue. Obviously for individuals like Ramon, resolving whether state law enforcement officers may grant federal civil immigration detainers and deprive them of their liberty is significant. A resolution on this issue is also in the interest of Montana taxpayers, considering the legal costs associated with challenges to local law enforcement detainer authority, as well as the additional costs of detaining individuals in county jails.
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[*P31] An immigration detainer effectuates a new restraint on an individual who otherwise would be free to leave the custody of a local law enforcement officer. Indeed, this Court has affirmatively held that when an individual is held for a new period of detention for a new purpose, such action is an arrest under § 46-7-101(1), MCA. State v. Norvell, 2019 MT 105, ¶¶ 7, 19, 395 Mont. 404, 440 P.3d 634. When Montana law enforcement personnel honor a DHS civil immigration detainer request that they hold a person for up to two days after he or she would otherwise be entitled to release from State custody, the result is a new seizure and arrest of the individual for a new purpose. See Lunn, 477 Mass. at 527-28, 78 N.E.3d at 1153; cf. Rodriguez v. United States, 575 U.S. 348, 352-53, 357, 135 S. Ct. 1609, 1613, 1616, 191 L. Ed. 2d 492 (2015) (holding that prolonging an individual’s detention for a new purpose when the person would otherwise be released constitutes a new seizure, even if it only prolongs the detention for “seven or eight minutes”).
[*P32] In this case, the immigration detainer and the Detention Center’s actions amounted to an arrest under Montana law. Like the facts in Norvell, the immigration detainer here resulted in a new detention for a new purpose. New detentions as a result of an immigration detainer meet the broad definition of an arrest, as well as the elements of an arrest under the Harrer decision. First, in refusing to release Ramon upon his bail bondsman’s attempt to post his bond, the Detention Center effectively took Ramon back into custody under the claimed purpose that there was an immigration detainer request by Border Patrol. Second, the Detention Center acted under Border Patrol’s federal authority in detaining Ramon. Third, actual and constructive detention occurred since the Detention Center’s statement that it would not release Ramon, even if he posted bond indicated the Detention Center’s intention to keep Ramon in its custody against his will when he was otherwise entitled to post bond and be released. Lastly, Ramon was conscious of the fact that the Detention Center would not allow his release due to the detainer request.
[*P33] Appellee’s and the United States’ argument that a detainer is only extending the original arrest and does not constitute a new arrest is incorrect. It is unquestionable that an individual in Ramon’s position would not have felt free to walk away under the circumstances. By informing Ramon’s bondsman that he would not be released upon posting of the bond, the Sheriff kept Ramon in custody for a new purpose after he was otherwise eligible to be released. But for the grant of the immigration detainer, a reasonable person, innocent of any crime, would have felt free to leave upon posting bond.