Who is Burke Marshall from A Testament of Hope: The Essential Writings and Speeches of Martin Luther King, Jr and what is their importance?

Burke Marshall was the chief civil rights assistant to the attorney general in 1963. He was sent to Birmingham to negotiate an end to the violence. Marshall did not have power to insist upon a solution, but he did have the backing of the president. As the negotiator between the civil rights leaders and the white leaders of the community, he was recognized as one who listened..... in return, others listened to him.