A hero of the 1960s was a lawyer with short hair, a starched white shirt and thin dark necktie, standing in a famous photograph before a line of armed police officers. It was at the funeral of Medgar Evars, gunned down because of civil rights advocacy, and John Doar was the white lawyer from the U.S. Department of Justice.

That scene in Jackson in 1963 deserves to live in American history. Doar, who died Tuesday at 92, pleaded with the protestors to avoid violence. Not just on that tense day was he one of the men who made a difference in the South.

He called himself a “Lincoln Republican,” a lost political category, but he worked for two Democratic presidents who were dragged into the national debate over civil rights. The Justice Department was a small agency in those days, and the civil rights debates of the 1950s had handcuffed its lawyers when it came to legal avenues to protect against “states rights” oppression of black citizens. Doar and his colleagues had other ideas.

Doar, who was awarded the Presidential Medal of Freedom in 2012, would eventually lead dramatic changes in the South. He escorted James Meredith onto the campus of the University of Mississippi in 1962. He was the lead prosecutor in the federal trial arising from the deaths of three civil rights workers, Andrew Goodman, James Chaney and Michael Schwerner.

The South and the nation owes him a debt of gratitude.