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Immigration Detention is Arbitrary

Last updated: July 21, 2023
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1. The U.S. System of Immigration Detention is Arbitrary under International Law Because it is Not Proportional, Reasonable or Necessary

Arbitrary detention is absolutely prohibited under international law. All major international and regional instruments relating to the protection and promotion of human rights contain the prohibition, including the International Covenant on Civil and Political Rights (ICCPR). Article 9 of the ICCPR provides that “No one shall be subjected to arbitrary arrest or detention. No one shall be deprived of his liberty except on such grounds and in accordance with such procedure as are established by law.” The prohibition is also part of legally binding customary international law. To avoid classification as arbitrary, immigration detention must be an exceptional measure of last resort. When it is used, it must be justified as proportionate, reasonable and necessary.

  • The U.S. Immigration Detention System Is Not Proportionate

    For immigration detention to be proportional, it must not be automatic or mandatory. The principle of proportionality requires that alternatives to detention be considered in every circumstance. In the U.S., immigration detention is imposed mandatorily on large swaths of migrants without individual assessment. Since the U.S. immigration system overtly and intentionally imposes mandatory detention on migrants without consideration of other less restrictive alternatives, it does not meet the proportionality requirement needed for immigration detention to not be arbitrary.
  • The U.S. Immigration Detention System is Not Reasonable

    For immigration detention to be considered reasonable, it must be used in pursuance of a legitimate aim of the state. In addition to facilitating imminent expulsion, legitimate purposes for immigration detention include a risk of the migrant absconding from future legal proceedings or administrative processes, presenting a danger to themselves or others, or posing a risk to national security. Detention for a short period of time may also be legitimate if used for the purposes of documenting entry, recording claims, or verifying identity. The U.S. however uses immigration detention for illegitimate purposes such as penalizing illegal entry and deterring migrants from entering the country and seeking asylum. Additionally, the U.S. immigration detention system is improperly influenced by economic incentives, including the meeting of “bed quotas” for private detention companies. Immigration detention imposed by the U.S. for these illegitimate purposes fails to meet the reasonableness requirement needed for immigration detention not to be considered arbitrary.
  • The U.S. Immigration Detention System is Not Necessary

    For immigration detention to be necessary, it must be “indispensable for achieving the intended purpose,” such that no other less restrictive means of achieving the purpose exists. Thus, international law requires that states make available to migrants alternatives to detention. A showing of necessity requires that less restrictive measures be considered prior to imposing detention. In considering alternatives to detention, States must fully consider individual circumstances. In the U.S., migrants are detained more than they are released despite alternatives to detention being available. In the U.S., not all migrants are subject to case-by-case assessments. Without such an individualized assessment showing the necessity of detention for each individual migrant, the U.S. immigration detention system fails to meet the necessity requirement needed for immigration detention not to be considered arbitrary.

Because the U.S. fails to demonstrate that immigration detention is in each case proportional, reasonable and necessary, the U.S. immigration detention system is arbitrary under international law.

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