To justify detention of immigrants for a period longer than six months, the government was required to show removal in the foreseeable future or special circumstances.

Amicus curiae briefs were filed by the Washington Legal Foundation on behalf of the government in the Zadvydas case and by the Legal Immigration Network, Inc., the American Association of Jews from the former USSR, the Lawyers Committee for Human Rights, the American Civil Liberties Union, Human Rights Watch, and Carolyn Patty Blum, et al., on behalf of Kim.

He noted that the statute grants the Attorney General the authority to detain a deportee past the term of the 90-day removal period, without judicial or administrative review.

[2][10] The government also argued that Congress had plenary power to enact such a law under its authority to control immigration, and that both the executive and judicial branches must defer to that decisionmaking.

[2][10][11] Substantive due process applied to aliens that resided within the United States, and absent a showing that they were a danger to society or a flight risk, they could not be detained.

He posited that Congress gave the Attorney General the express authority to order continued detention, and added that the majority misapplied the concept of statutory construction, noting that the court could only distinguish between plausible interpretations.

[3][9] Civil libertarians have noted that over 2,000 aliens have been held indefinitely without hope of repatriation[14] and that the Department of Homeland Security holds approximately 31,000 immigrants in detention at any given time.

[15] It has been noted that 20 years prior to the Zadvydas decision, approximately 122,000 Mariel Cubans had been paroled into the United States after facing indefinite detention.

[16] This case also allowed deportee Binh Thai Luc to be released from immigration detention after his native Vietnam declined to offer the U.S. government travel documents.

[17] Zadvydas was also cited by the 9th Circuit three-judge appeals panel on February 9, 2017, in Washington v. Trump, with regard to an executive order concerning the restriction of immigration from certain stipulated countries.

In that case, the 9th Circuit panel referred to the Zadvydas opinion "emphasizing that the power of the political branches over immigration 'is subject to important constitutional limitations'.

[19] Zadvydas was cited in a subsequent Supreme Court case, Clark v. Martinez,[20] that reiterated the principle that all people within the United States were entitled to due process and could not be deprived of liberty indefinitely.

[22] Three experts had lent support to the legislation during a hearing on the Act: Gary Mead, Executive Associate Director for ICE's Enforcement and Removal Operations; Thomas H. Dupree, Jr., partner at Gibson, Dunn & Crutcher LLP (and former Principal Deputy Assistant Attorney General under President Bush); and Ft. Myers Chief of Police Douglas Baker, a colleague of Officer Widman who was murdered by an alien released as a result of Zadvydas.

1932, would strip important due process protections of harmless individuals by needlessly increasing the government's already broad authority to detain noncitizens."

Joanne Lin, legislative counsel for the American Civil Liberties Union (ACLU), stated that the bill would have authorized indefinite detention of immigrants without providing procedural safeguards.