On the night of the 10th to the 11th of August 1936 a group militia men, together with Angel Samblancat, Josep Maria Batlle and Antonio Devesa of the CNT prisoner support committee, occupied the Palace of Justice, proceeding to revise socio-political cases, to return deposits and to answer queries. By the Decree of 17th August the Barcelona Law Office was created. Due to Angel Samblancat being named Magistrate, Eduardo Barriobero was designated Chief Counsel. The cases taken on by the Law Office covered civil, labour and trade issues, usury ( all cases from before the 19th July), and family matters (divorce, matrimony and the protection of minors and the disabled). Eduardo Barriobero led the repression against those against the the Republican regime. Days later the Gerona and Tarragona Law Offices were created with the same powers as the Barcelona Law Office, with delegations in Badalona, Granollers, Manresa, Mataró and Tortosa. By the Decree of 18th November the Law Offices were dissolved, their cases and documents distributed between various Courts and, by the Order of the 12th December, their sentences were validated, dictating the rules of procedure for the cases which had not yet been sentenced or carried out. In 1937 four members of the Barcelona Law Office were accused. They were tried by the Supreme Court and acquitted. Nevertheless in 1939 the victors of the war accused them of theft, coercion and threats which lead to a 17 ½ year period of research and investigation on this case. The charge was finally rescinded without the evidence of any file statement. When the war ended a series of resolutions were enacted that declared null and void all of the legal actions taken during the Republic. There is no evidence of any sentence from any Law Office revised or revoked. This thesis aims to reconstruct, by means of a systematic search of print sources (ACTSJC, ANC, AHN, county and municipal court records), the history of this unique law institution. The consulted documents, above all the court records, have allowed us to have a partial picture of the Barcelona Law Office, as well as that of Granollers, as they are the only offices where records still exist. Each of the cases found has been studied thoroughly in order to understand the competence, jurisdiction and procedure employed by Law Offices, which represented complications and peculiarities with respect to ordinary justice. In order to understand the ideas that might have inspired this movement I have studied the theory. In order to understand the ideas that might have inspired this movement I have studied the theory, principles of law and thinkers of that period which undoubtedly influenced them. Concepts such as fast justice, free, Judge as proceeding’s promoter, Judge’s awareness and judgment, natural law and equity are amongst some legal concepts at the time. This thesis is structured as follows: 1. Triumph of revolutionary law. 2. Powers of the Legal Office in Barcelona. 3. Proceeding of Barcelona Law Office. 4. Other Law Offices in Catalonia. 5. Triumph of Republican bourgeois law. 6. Triumph of rebel’s law. 7. Major figures of this movement and their tragic outcome.