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
Court Case
May 2023
National Security
Privacy & Technology
The Warrant Clause in the Digital Age
The information generated by today’s digital devices and online services reveals private matters far beyond what one could learn from physical analogs. In a series of legal filings and a white paper, available below, the ACLU has argued that to keep apace with technological developments and adequately protect our privacy, the Fourth Amendment's warrant requirement must be interpreted robustly. Seizures and searches of digital data must be cabined to probable cause, limited to specific categories of information relevant to the investigation, and closely overseen by a neutral magistrate.
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Court Case
May 2023
National Security
Privacy & Technology
The Warrant Clause in the Digital Age
The information generated by today’s digital devices and online services reveals private matters far beyond what one could learn from physical analogs. In a series of legal filings and a white paper, available below, the ACLU has argued that to keep apace with technological developments and adequately protect our privacy, the Fourth Amendment's warrant requirement must be interpreted robustly. Seizures and searches of digital data must be cabined to probable cause, limited to specific categories of information relevant to the investigation, and closely overseen by a neutral magistrate.
Court Case
Apr 2023
National Security
Privacy & Technology
ACLU v. FBI - FOIA Case for FBI Records Related to Nondisclosure Agreements for Cell Site Simulators
In 2021, the ACLU submitted a FOIA request to the FBI to determine whether the FBI has continued to require state and local law enforcement agencies to enter into nondisclosure agreements before purchasing or using cell site simulators. After appealing and suing, the ACLU finally obtained responsive records confirming that the FBI has continued to impose nondisclosure agreements on law enforcement agencies seeking to use the FBI’s cell site simulators.
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Court Case
Apr 2023
National Security
Privacy & Technology
ACLU v. FBI - FOIA Case for FBI Records Related to Nondisclosure Agreements for Cell Site Simulators
In 2021, the ACLU submitted a FOIA request to the FBI to determine whether the FBI has continued to require state and local law enforcement agencies to enter into nondisclosure agreements before purchasing or using cell site simulators. After appealing and suing, the ACLU finally obtained responsive records confirming that the FBI has continued to impose nondisclosure agreements on law enforcement agencies seeking to use the FBI’s cell site simulators.
U.S. Supreme Court
Feb 2023
National Security
+2 Issues
Twitter, Inc., v. Taamneh
The Supreme Court will decide whether a social media or other platform can be liable for “aiding and abetting” a terrorist attack merely because it failed to adequately block content valorizing terrorism, even where the platform has policies barring terrorist content.
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U.S. Supreme Court
Feb 2023
National Security
+2 Issues
Twitter, Inc., v. Taamneh
The Supreme Court will decide whether a social media or other platform can be liable for “aiding and abetting” a terrorist attack merely because it failed to adequately block content valorizing terrorism, even where the platform has policies barring terrorist content.
U.S. Supreme Court
Feb 2023
National Security
Wikimedia v. NSA - Challenge to Upstream Surveillance
The ACLU is challenging the constitutionality of the NSA’s mass interception and searching of Americans’ international Internet communications. At issue is the NSA’s “Upstream” surveillance, through which the U.S. government systematically monitors private emails, messages, and other data flowing into and out of the country on the Internet’s central arteries. The ACLU’s lawsuit was brought on behalf of the Wikimedia Foundation and eight legal, human rights, and media organizations, which together engage in trillions of sensitive communications and have been harmed by Upstream surveillance.
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U.S. Supreme Court
Feb 2023
National Security
Wikimedia v. NSA - Challenge to Upstream Surveillance
The ACLU is challenging the constitutionality of the NSA’s mass interception and searching of Americans’ international Internet communications. At issue is the NSA’s “Upstream” surveillance, through which the U.S. government systematically monitors private emails, messages, and other data flowing into and out of the country on the Internet’s central arteries. The ACLU’s lawsuit was brought on behalf of the Wikimedia Foundation and eight legal, human rights, and media organizations, which together engage in trillions of sensitive communications and have been harmed by Upstream surveillance.
Court Case
Dec 2022
National Security
Sherry Chen v. United States
In October 2021, the ACLU joined the legal team representing Sherry Chen, an award-winning Chinese American scientist who was wrongfully investigated, prosecuted, and terminated from her job as a hydrologist with the National Weather Service. The government accused Ms. Chen of unlawfully downloading sensitive government data and falsely portrayed her as a spy for China. On the eve of trial, the Justice Department dropped all charges against her. In 2019, Ms. Chen filed a federal lawsuit against the United States, seeking accountability for the government’s misconduct. In December 2022, Ms. Chen reached a historic settlement of her federal lawsuit and a separate case before the Merit Systems Protection Board, an agency that hears claims from federal employees. The settlement, one of the largest paid to an individual plaintiff in Commerce Department history, includes compensation valued at approximately $1.8 million.
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Court Case
Dec 2022
National Security
Sherry Chen v. United States
In October 2021, the ACLU joined the legal team representing Sherry Chen, an award-winning Chinese American scientist who was wrongfully investigated, prosecuted, and terminated from her job as a hydrologist with the National Weather Service. The government accused Ms. Chen of unlawfully downloading sensitive government data and falsely portrayed her as a spy for China. On the eve of trial, the Justice Department dropped all charges against her. In 2019, Ms. Chen filed a federal lawsuit against the United States, seeking accountability for the government’s misconduct. In December 2022, Ms. Chen reached a historic settlement of her federal lawsuit and a separate case before the Merit Systems Protection Board, an agency that hears claims from federal employees. The settlement, one of the largest paid to an individual plaintiff in Commerce Department history, includes compensation valued at approximately $1.8 million.