Multiple functions of immigration detention: Police measures in the governance of mobile populations

Notwithstanding punitive implications, immigration detention as an administrative deprivation of liberty represents a characteristic police measure, targeting deportable noncitizens with limited rights and protections. Drawing on an analysis of the detention system in Finland, I discuss different functions of immigration detention, focusing on police powers in the governance of mobile populations. In Finland, immigration detention is separated from the criminal justice system and delegated to the police, who possess broad powers to impose coercive measures for the enforcement of immigration decisions and social control in the absence of effective judicial supervision. Despite being affiliated with the removal of rejected asylum seekers, immigration detention also is intertwined with crime prevention and control of irregular migration. In addition to deprivation of liberty in the first place, police measures support removal procedures that continue during detention, as well as other administrative strategies to control deportable people and deter unauthorized residency, involving varying degrees of coercion. Though connected with criminal justice and manifestations of penal power in border criminology discussions, immigration detention can arguably be better understood as a coercive police measure, which can be employed alongside other administrative means for immigration enforcement outside of the criminal justice system.