Prior to joining the Legislature, Assemblymember Gabriel was a Los Angeles County Commissioner and constitutional rights attorney. Through his legal work and legislative advocacy, Gabriel has assisted Holocaust survivors, victims of domestic abuse, and communities facing hate-motivated violence, and helped to resolve complex business disputes. From 2008 to 2010, Gabriel was a senior advisor to former United States Senator Evan Bayh.

A committed environmental and longtime community activist, Gabriel serves on the boards of the Los Angeles League of Conservation Voters and the Jewish Federation of Greater Los Angeles. He lives in Encino with his wife Rachel Rosner, an affordable housing attorney, and their sons Ethan and Joshua.