The Lex Talionis Fraternitas was founded on September 29, 1969 by 35 students of the San Beda College of Law.Policarpio Martinez and six other founders were requested to write the draft of the fraternity's constitution and by-laws.

After a brief debate, the founders approved the document and sealed it with a sprinkling of beer in the afternoon of September 28, 1969 at the members' favorite bar near San Beda.

Miguel Soriano, Rizal Guerrero, and Jose Mendoza were unanimously elected and proclaimed as the first Grand Judexes of the Troika of the Lex Talionis Fraternitas.

A senior advisory body, the Council of Grand Judexes, likewise takes an active part in the affairs of the fraternity and acts as the corporate Board of Directors.

On September 8, 1991, fraternity neophyte Raul Camaligan died of physical injuries sustained from initiation rites with Lex Talionis.

Records of the criminal case show Camaligan, along with three other freshmen from the San Beda College of Law, were recruited with the assurance that hazing would not be required for full membership.

"[5] Additionally, the petitioners submitted evidence that a scholarship foundation in honor of Raul Camaligan was established in 1995 by the fraternity members.

[9] However, in 2017, an investigation by the Philippine Daily Inquirer revealed that no such foundation was ever established and no scholars were registered under its name, according to the records of San Beda College.

[5] Gilbert Camaligan, Raul's father, further condemned the fraternity's silence after 25 years, and claimed the organization is "not a good example for young people.

[10][11][12] Within the first year of Duterte's presidency, 25 members of Lex Talionis held key positions in the government, up from just two during the previous administration.