FLAG was founded in October 1974 at the home of Sen. Jose W. Diokno,[13] together with Sen. Lorenzo M. Tañada,[14] Justice J.B.L. Reyes,[4] and Atty. Joker Arroyo[8] - more than two years after the 1972 proclamation of Martial law under Ferdinand Marcos. Diokno had conceived the law firm during his imprisonment. After his release on September 11, 1974, which came after spending 718 days as a political prisoner under the Marcos administration, he organized FLAG with his friend, retired Sen. Tañada and a group of young lawyers.[15] The group was conceived as a means of supporting human rights victims through a new and innovative method called developmental legal aid or developmental legal advocacy. FLAG member Atty. Arno Sanidad later stated that in 1976, he was among the five lawyers from the University of the Philippines Diliman to serve as the first paralegals in the country, under the guidance of Diokno and FLAG.[16]
During the dictatorship, FLAG defended farmers, similar victims of agrarian reform, and activists who were victims of paramilitary abuses, with Diokno noted to have helped even further by giving allowances to clients without any financial means.[17] Most cases at this time regarding human rights abuses were handled by FLAG, in coordination with smaller groups such as the Task Force Detainees of the Philippines. Human Rights Primers were also an integral aspect of the advocacy of human rights that FLAG initiated in the Philippines.[18]
FLAG's activities sometimes placed lawyers working with them at risk. Among the (at least) twelve FLAG lawyers murdered during the dictatorship[19] were Zorro Aguilar, Romraflo Taojo, Vicente Mirabueno,[20] and Crisostomo Cailing, all of whom have since been honored by having their names inscribed on the wall of remembrance at the Philippine Bantayog ng mga Bayani, which honors the martyrs and heroes who fought against the Marcos dictatorship's authoritarian rule.[21] FLAG has handled cases such as the 1984 case of the "Negros Nine" kidnapped military victims of Marcos.
FLAG continued to handle leading human rights cases including the death penalty case of Leo Echegaray in 1999.[1][22] FLAG also represented the Manalo brothers and won the first writ of amparo case in 2008, which was a legal writ first proposed in the Philippines by Senator Diokno in the 1980s.[23]
Among the recent advocacies of FLAG has been to help stem the tide of extrajudicial killings linked to the Philippine drug war started by President Rodrigo Duterte.[26][27] There have also been cases linked to the libel case of Maria Ressa, as well as the Anti-Terror Law of 2020.[28] FLAG lawyers Chel Diokno and Sanidad petitioned to declare Section 4(e) as unconstitutional, for defining terrorism as excluding advocacy, protest, dissent, and similar actions "not intended to cause death or serious physical harm to a person, to endanger a person's life, or to create a serious risk to public safety." The Supreme Court agreed to declare it as unconstitutional for being overbroad.[29]
Zorro Aguilar, activist, newspaper editor, and human rights lawyer from Dipolog, Zamboanga, who became a martyr during the late years of Marcos's militaristic regime.[19] He is one of the first 65 names inscribed on the wall of remembrance at the Bantayog ng mga Bayani, which honored him as a martyr of the resistance against the dictatorship;
Jejomar Binay, vice-president, Chair of the Metro Manila chapter in the 1970s;[32]
David Bueno, human rights lawyer, martial law activist, and martyr who defended Martial Law victims in Ilocos Norte, which was the native province of Ferdinand Marcos. He is one of the first 65 names inscribed on the wall of remembrance at the Bantayog ng mga Bayani, which honored him as a martyr of the resistance against the dictatorship;
Rosario "Chato" Olivas-Gallo, Tañada-Diokno School of Law vice-dean, children's rights activist, and CEO of Christian Solidarity Worldwide, which is a human rights organization that protects persecuted Christians and is based in Hong Kong. Olivas-Gallo through Christian Solidarity Worldwide has also called for freer democratic processes in developing countries;[35]
Arno Sanidad, FLAG Deputy Secretary General, law professor, and member of the Regional Council on Human Rights in Asia whose law office serves as FLAG's mailing address for filed grievances concerning abuse and reports of human rights violations;
Romraflo Taojo, Filipino labor and human rights lawyer, activist, and educator killed on April 2, 1985, when an unidentified gunman believed to be part of a paramilitary group acting on orders from the military shot him at his apartment in Tagum, Davao del Norte. He is one of the first 65 names inscribed on the wall of remembrance at the Bantayog ng mga Bayani, which honored him as a martyr of the resistance against the dictatorship;
Francisco, Katerina (February 20, 2017). "Meet Lascañas' battle-tested FLAG lawyers". Rappler. Retrieved June 18, 2020. Founded in 1974 by the late senators Jose W. Diokno, Lorenzo Tañada Sr., and Joker Arroyo, FLAG provided free legal services to victims of martial law during the Marcos years.