He began his law career by engaging in private law practice, mostly in labor law, with the Siguion Reyna Montecillo & Ongsiako Law Offices from 1975 to 1982. At the same time, he shared his legal knowledge in the academe as a member of the Ateneo de Manila University Faculty of Law from 1976 to 1981, and in 1986.  He entered government service in 1982 as Executive Director of the Institute of Labor and Manpower Studies under the Philippine Ministry of Labor until 1984, when he went on to become Vice-Chair of the Labor and Employment Committee of the Mambabatas Pambansa, Philippine National Assembly.  He became Deputy Minister of Labor for Legal and Legislative Affairs from 1985 to 1986 before returning to private practice as Senior Partner of the Natividad Delos Reyes Maambong & Brion Law Firm from 1986 to 1988, and subsequently of Siguion Reyna from 1995 to 2001.  During this time, he worked as a consultant for the Civil Service Commission on public sector unionism, leading to the paper “Public Sector Unionism – a Proposed Reconfiguration,” and returned to teach at Ateneo Law from 1995 to 1997. He went back to full-time government service in 2001 when he was appointed Undersecretary of Labor for Labor Relations of the Department of Labor and Employment and subsequently Undersecretary of Foreign Affairs for Special Projects of the Department of Foreign Affairs a year after.  He likewise taught at the University of the Philippines School of Labor and Industrial Relations from 2001 to 2002 and the Far Eastern University Institute of Law from 2005 to 2006.

Justice Brion, the son of retired Regional Trial Court Judge Edon B. Brion and Laura S. Dizon, crossed from Bar to Bench when he was appointed CA Associate Justice in July 2003.  He remained a Senior Member of the Appellate Court’s 15th Division until June 2006, before accepting the task of leading the country’s Department of Labor and Employment that July.  He has since joined the Judiciary anew to complete the 15-member High Tribunal, filling in the vacancy left by the retirement of Justice Angelina Sandoval-Gutierrez last February 27.

Although born in Manila on December 29, 1946, Justice Brion is a true-born son of San Pablo, Laguna, the City of Seven Lakes, whose people value the pursuit of excellence in all fields.  He graduated with a Bachelor of Arts in Mathematics degree from the San Pablo Colleges before going on to take his law studies at the Ateneo de Manila University, where he became Editor in Chief of the Ateneo Law Journal.  He graduated with a Bachelor of Laws degree from the Ateneo in 1974 cum laude as well as class valedictorian and awardee of the Golden Leaf Award, Gold Medal for Academic Excellence, and First Honors Gold Medal. He went on to place first in the Bar Examinations held that same year, with a grade of 91.65%. 

Despite this seeming pinnacle of achievement, Justice Brion never ceased in his pursuit of knowledge.  In the midst of a burgeoning legal career, he went on to obtain his Master of Laws degree at the Osgoode Hall Law School of York University in Toronto, Canada in 1994, with Labor Law as his main area of study.  There, he became the Editor in Chief of Legal Update, a publication of the Legal Services Branch of the Ontario Ministry of Labor from 1992 to 1993.  While serving as a magistrate of the appellate court, Justice Brion enrolled in Spanish language classes at the Instituto Cervantes de Manila, from 2005 to 2006, finishing Nivel (level) 10.

Justice Brion is married to chemist-lawyer Atty. Antonietta C. Articona-Brion, who is presently a CA Court Attorney.  They are blessed with two similarly multi-skilled children, Antonella A. Brion, a historian with a Bachelor of Arts degree in History from York University in Toronto, Canada, presently engaged in Information Technology, and Arturo Brion, Jr., a computer engineering graduate of McMaster University and Bachelor of Laws degree holder from the University of New Brunswick, now engaged in Intellectual Property Law Practice in Ottawa, Canada.

Justice Brion is a member of the Integrated Bar of the Philippines, Philippine Bar Association, and the Law Society of Upper Canada.  He was Chapter President of the IBP, Laguna Chapter from 1981 to 1983, National President of the YMCA of the Philippines in 1985, and a member of its National Board in 2006.  He is also a member of the Free and Accepted Masons.