Gray began his legal career as a sole practitioner, less than a year out of law school, and at age twenty-four, he represented Mrs. Rosa Parks who refused to give up her seat to a white man on a city bus, the action that initiated the Montgomery Bus Boycott. Gray was also Dr. Martin Luther King, Jr.'s first civil rights lawyer. This was the beginning of a legal career that now spans over forty-five years.

Determined to right the wrongs he found in his native State of Alabama, Gray has been at the forefront of changing the social fabric of America regarding desegregation, integration, constitutional law, racial discrimination in voting, housing, education, jury service, farm subsidies, medicine and ethics, and generally in improving the national judicial system.