Joseph Earl Marshall, Jr. (born 1947) is an American author, lecturer, radio talk show host, and community activist. Marshall grew up in St. Louis, Missouri and the South Central part of Los Angeles, California. He graduated from Loyola High School of Los Angeles, the University of San Francisco with a BA in political science and sociology (1968), San Francisco State University in 1974 with an M.A. in Education, and the Wright Institute with a Ph.D. in Psychology. Marshall became a teacher at Woodrow Wilson High School of San Francisco in 1969 after getting his B.A. In 1994, Marshall left his teaching job to become an anti-violence activist.