National Security
CAIR-Foundation, Inc and CAIR Florida, Inc. v. DeSantis et al.
The ACLU, the ACLU of Florida, the Southern Poverty Law Center, and their partners represent CAIR and CAIR-Florida in two federal lawsuits challenging Governor DeSantis’s unconstitutional and baseless designation of the nonprofits as “terrorist.” The lawsuits allege violations of CAIR and CAIR-Florida’s rights under the First Amendment and the due process clause of the Fourteenth Amendment.
Status: Ongoing
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Court Case
Jul 2026
National Security
Human Rights
FOIA Case Seeking the Trump Administration’s Legal Justification for Deadly Boat Strikes
The Department of Justice’s Office of Legal Counsel (“OLC”) authored a legal opinion that reportedly claims to justify the Trump administration’s illegal lethal strikes on civilians in boats in the Caribbean Sea and eastern Pacific Ocean. Media reports indicate that, in addition to claiming that the strikes are lawful acts in an alleged “armed conflict” with unspecified drug cartels, the OLC opinion also purports to immunize personnel who authorized or took part in the strikes from future criminal prosecution. Because the public deserves to know how our government is justifying these illegal strikes, and why they think the people who carried them out should not be held accountable, the ACLU is seeking immediate release of the OLC legal opinion and related documents pursuant to the Freedom of Information Act.
U.S. Supreme Court
Dec 2023
National Security
FBI v. Fikre
Whether the government can overcome the voluntary cessation exception to mootness by removing an individual from the No Fly List when the government has not repudiated its decision to place him on the List and remains free to return him to the List for the same reasons and using the same procedures he alleges were unlawful.
Florida
Nov 2023
National Security
+2 Issues
Students for Justice in Palestine at the University of Florida v. Raymond Rodrigues
The University of Florida chapter of Students for Justice in Palestine filed a lawsuit on November 16, 2023, challenging the Chancellor of the State University System of Florida’s order to state universities to deactivate the student group. This order threatens the students’ constitutionally-protected right to free speech and association in violation of the First Amendment. The ACLU and its partners are seeking a preliminary injunction that would bar the Chancellor and the University of Florida from deactivating the UF SJP.
U.S. Supreme Court
Apr 2022
National Security
+2 Issues
FBI v. Fazaga
In a case scheduled to be argued before the U.S. Supreme Court on November 8, 2021, three Muslim Americans are challenging the FBI’s secret spying on them and their communities based on their religion, in violation of the Constitution and federal law. In what will likely be a landmark case, the plaintiffs — Yassir Fazaga, Ali Uddin Malik, and Yasser Abdelrahim — insist that the FBI cannot escape accountability for violating their religious freedom by invoking “state secrets.” The plaintiffs are represented by the Center for Immigration Law and Policy at UCLA School of Law, the ACLU of Southern California, the American Civil Liberties Union, the Council for American Islamic Relations, and the law firm of Hadsell Stormer Renick & Dai.
U.S. Supreme Court
Jul 2021
National Security
Immigrants' Rights
Sierra Club v. Trump — Challenge to Trump’s National Emergency Declaration to Construct a Border Wall
In February 2019, the ACLU filed a lawsuit challenging President Trump’s emergency powers declaration to secure funds to build a wall along the southern border. The lawsuit was filed on behalf of the Sierra Club and the Southern Border Communities Coalition. The lawsuit argues that the president is usurping Congress’s appropriations power and threatening the clearly defined separation of powers inscribed in the Constitution. On January 20, 2021, President Biden halted further border wall construction. Litigation in this and subsequent related challenges has been paused or deadlines extended while the ACLU’s clients and the Biden administration determine next steps.
Indiana
Oct 2016
National Security
Immigrants' Rights
Exodus Refugee Immigration, Inc. v. Mike Pence, et al
The American Civil Liberties Union and the ACLU of Indiana, on behalf of Exodus Refugee Immigration, filed suit against Governor Mike Pence and the secretary of the Indiana Family and Social Services Administration to stop attempts to suspend resettlement of Syrian refugees, claiming the governor’s actions violate the United States Constitution and federal law.
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156 National Security Cases
Virginia
Aug 2026
National Security
Privacy & Technology
In Re: Application of The United States Of America for an Order Pursuant To 18 U.S.C. § 2703(d)
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Virginia
Aug 2026
National Security
Privacy & Technology
In Re: Application of The United States Of America for an Order Pursuant To 18 U.S.C. § 2703(d)
Virginia
Jul 2026
National Security
Trabelsi v. Crawford, et al. – Lawsuit Challenging Unlawful Detention and Inhumane Treatment of Acquitted Man
Our client, Nizar Trabelsi, was being held in the United States against his will. The federal government brought him here from Belgium in 2013 and charged him with terrorism-related crimes. At trial, the government’s case failed: a federal jury found Mr. Trabelsi not guilty. But instead of allowing Mr. Trabelsi to return to Belgium after his acquittal, the United States placed him in highly restrictive immigration detention and began an ongoing effort to force him to Tunisia, where he was born and where he would very likely be tortured.
Mr. Trabelsi’s detention violated the Constitution, immigration law, and the extradition treaty between the United States and Belgium. Through this lawsuit, he sought to return to Belgium, and he demanded an immediate improvement of his detention conditions. In 2025, at long last, the United States removed him from detention and returned him to Belgium.
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Virginia
Jul 2026
National Security
Trabelsi v. Crawford, et al. – Lawsuit Challenging Unlawful Detention and Inhumane Treatment of Acquitted Man
Our client, Nizar Trabelsi, was being held in the United States against his will. The federal government brought him here from Belgium in 2013 and charged him with terrorism-related crimes. At trial, the government’s case failed: a federal jury found Mr. Trabelsi not guilty. But instead of allowing Mr. Trabelsi to return to Belgium after his acquittal, the United States placed him in highly restrictive immigration detention and began an ongoing effort to force him to Tunisia, where he was born and where he would very likely be tortured.
Mr. Trabelsi’s detention violated the Constitution, immigration law, and the extradition treaty between the United States and Belgium. Through this lawsuit, he sought to return to Belgium, and he demanded an immediate improvement of his detention conditions. In 2025, at long last, the United States removed him from detention and returned him to Belgium.
Maine
May 2026
National Security
Free Speech
Smith v. Trump
On April 11, 2025, the ACLU and ACLU of Maine filed a lawsuit on behalf of two human rights advocates who, because of an executive order signed by President Trump, have been forced to stop humanitarian work with the International Criminal Court.
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Maine
May 2026
National Security
Free Speech
Smith v. Trump
On April 11, 2025, the ACLU and ACLU of Maine filed a lawsuit on behalf of two human rights advocates who, because of an executive order signed by President Trump, have been forced to stop humanitarian work with the International Criminal Court.
Court Case
Feb 2026
National Security
ACLU v. Department of Homeland Security (CP3 FOIA)
In 2021, the Department of Homeland Security announced the establishment of the Center for Prevention Programs and Partnerships, also known as CP3, and a domestic terrorism branch within the Office of Intelligence and Analysis. These initiatives are a product of DHS's new measures to address domestic violent extremism, and little is known about these programs and the effects they'll have on members of the public. DHS has a history of similar harmful programs, which have targeted communities of color, immigrants and Muslim communities. The public has a right to know about the impacts of CP3 and the I&A domestic terrorism branch on the civil rights, liberties and privacy of communities of color, immigrants and other marginalized communities. In 2022, the ACLU submitted a FOIA request to compel the government to release information about these initiatives. It is imperative that the public gain a greater understanding about the policies, practices, methods and goals of both CP3 and the I&A domestic terrorism branch. After DHS produced records, the ACLU dismissed the case in February 2026.
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Court Case
Feb 2026
National Security
ACLU v. Department of Homeland Security (CP3 FOIA)
In 2021, the Department of Homeland Security announced the establishment of the Center for Prevention Programs and Partnerships, also known as CP3, and a domestic terrorism branch within the Office of Intelligence and Analysis. These initiatives are a product of DHS's new measures to address domestic violent extremism, and little is known about these programs and the effects they'll have on members of the public. DHS has a history of similar harmful programs, which have targeted communities of color, immigrants and Muslim communities. The public has a right to know about the impacts of CP3 and the I&A domestic terrorism branch on the civil rights, liberties and privacy of communities of color, immigrants and other marginalized communities. In 2022, the ACLU submitted a FOIA request to compel the government to release information about these initiatives. It is imperative that the public gain a greater understanding about the policies, practices, methods and goals of both CP3 and the I&A domestic terrorism branch. After DHS produced records, the ACLU dismissed the case in February 2026.
Massachusetts
Jan 2026
National Security
Human Rights
Burnley v. U.S.: Demanding Accountability on Caribbean Boat Strikes
On October 14, 2025, the United States military carried out an illegal missile strike that killed Chad Joseph and Rishi Samaroo, two Trinidadian men who were traveling by boat from Venezuela to their homes in Las Cuevas, Trinidad and Tobago. The American Civil Liberties Union, the Center for Constitutional Rights, the American Civil Liberties Union of Massachusetts, and Professor Jonathan Hafetz of Seton Hall Law School filed suit on behalf of Lenore Burnley, Mr. Joseph’s mother, and Sallycar Korasingh, Mr. Samaroo’s sister, seeking redress and accountability for these extrajudicial killings pursuant to the Death on the High Seas Act and the Alien Tort Statute.
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Massachusetts
Jan 2026
National Security
Human Rights
Burnley v. U.S.: Demanding Accountability on Caribbean Boat Strikes
On October 14, 2025, the United States military carried out an illegal missile strike that killed Chad Joseph and Rishi Samaroo, two Trinidadian men who were traveling by boat from Venezuela to their homes in Las Cuevas, Trinidad and Tobago. The American Civil Liberties Union, the Center for Constitutional Rights, the American Civil Liberties Union of Massachusetts, and Professor Jonathan Hafetz of Seton Hall Law School filed suit on behalf of Lenore Burnley, Mr. Joseph’s mother, and Sallycar Korasingh, Mr. Samaroo’s sister, seeking redress and accountability for these extrajudicial killings pursuant to the Death on the High Seas Act and the Alien Tort Statute.