Matthew Segal with the Constitution


Legal Director



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Matthew Segal has been legal director of the ACLU of Massachusetts since 2012. He leads a team of civil rights lawyers, and he has litigated cases on wrongful convictions, privacy, the criminalization of poverty, the First Amendment, and mandatory minimum sentencing.

Matt’s cases at the ACLU include Louhghalam v. Trump, the Boston lawsuit that temporarily halted President Trump's Muslim ban; Bridgeman v. District Attorney, which overturned a record 21,587 wrongful convictions tainted by chemist Annie Dookhan; and Commonwealth v. Augustine, which made Massachusetts the second state to recognize constitutional protections for cell phone location data. Previously, as an assistant federal defender in Asheville, North Carolina, Matt argued federal criminal appeals. One of those appeals led to hundreds of exonerations and resentencings and was profiled in the USA Today investigation Locked up but Innocent?

Matt was named a 2015 Massachusetts Lawyer of the Year by Massachusetts Lawyers Weekly, and in December 2016 he was elected to membership in the American Law Institute. He earned his J.D. from Yale Law School and his B.A., in mathematics and sociology, from Brandeis University. He clerked for the Honorable Raymond C. Fisher of the Ninth Circuit.

Criminal Justice

  • Argued cases leading to the dismissal of 21,587 wrongful convictions in the Annie Dookhan lab scandal Bridgeman v. District Attorney, 476 Mass. 298 (2017); Bridgeman v. District Attorney, 471 Mass. 465 (2015); Commonwealth v. Charles, 466 Mass. 63 (2013).
  • Argued case challenging the constitutionality of mandatory minimum sentencing. Commonwealth v. Laltaprasad, 475 Mass. 692 (2016).
  • Argued case leading to reversal of hundreds of wrongful convictions and sentences. US v. Simmons, 649 F.3d 237 (4th Cir. 2011) (en banc).

Privacy & Technology

  • Helped to uncover 63 cases in which the government sought to compel Apple or Google to assist the government in accessing data stored on a mobile device.
  • Argued Massachusetts case holding that state and local police must get a warrant before obtaining two weeks’ worth of a person’s cell site location information (CSLI). Commonwealth v. Augustine, 467 Mass. 230 (2014

Criminalization of Poverty

  • Participated in amicus briefing on the criminalization of poverty in Massachusetts. Commonwealth v. Henry, 475 Mass. 117 (2016); Commonwealth v. Magadini, 474 Mass. 593 (2016).
  • Argued case ending a federal district’s unlawful practice of ordering indigent federal defendants to repay the costs of their court-appointed attorneys. US v. Moore, 666 F.3d 313 (4th Cir. 2012).

First Amendment

  • Filed case challenging a Massachusetts law that requires people to alert the police before exercising their First Amendment right to record police officers performing their duties in public. Martin v. Evans (D. Mass. filed June 2016).
  • Co-counseled successful challenges to anti-panhandling ordinances in Lowell and Worcester, which infringed on the First Amendment right to beg.

Racial Justice & Immigrants’ Rights

  • Argued Louhghalam v. Trump, 2017 WL 386550 (D. Mass. 2017), which for seven days halted President Trump's first Muslim Ban.
  • Participated in public records advocacy and amicus briefing in groundbreaking decision holding that Black men in Boston might have logical reasons to flee the police. Commonwealth v. Warren, 475 Mass. 530 (2016).
  • Argued case on behalf of a U.S. military veteran wrongfully subjected to mandatory immigration detention. Casteneda v. Souza, 810 F.3d 15 (1st Cir. 2015) (en banc).

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