Back in high school we talked about him as an important figure in the Mexican-American community. He isn't just an actor but a socially and politically active/conscious figure.
If you ignore wikipedia as the source:
Olmos has often become involved in social issues, especially those affecting the Hispanic-American community in the United States. In 1998 Olmos founded Latino Public Broadcasting and currently serves as its Chairman. The Latino Public Broadcasting funds programming for public television which focuses on issues affecting Hispanic-Americans and advocates for diverse prespectives in public television. Also, in 1998, Olmos starred in the uplifting and Latino movie The Wonderful Ice Cream Suit, that breaks stereotypes and transcends the normal stigmas of most Latino oriented movies. Olmos also makes frequent appearances at juvenile halls and detention centers to speak to teenagers at risk. He has also been an international ambassador for UNICEF. In 2001, he was arrested and spent 20 days in prison for taking part in the Navy-Vieques protests against United States Navy target practice bombings of the island of Vieques, Puerto Rico.