During his senior year at Virginia Union, Marsh testified on behalf of the student government at a joint session of the Virginia General Assembly. Despite the U.S. Supreme Court ruling in "Brown v. Board of Education", the Virginia legislature, consisting of all white members, was considering laws to enact the Byrd Organization's program of "massive resistance" to desegregation. While there, Marsh met civil rights attorney Oliver Hill, who had also testified against the plan. Hill urged him to go to law school.