Who is L. Matthew Barr from The Pelican Brief and what is their importance?

L. Matthew Barr is commander of "The Unit," a $4 million arm of the Committee to Reelect the President (CRP), Barr is an ex-Marine, ex-CIA, ex-spy, and ex-felon, employed by Fletcher Coal, White House Chief of Staff. As ordered, Barr bugs the car and apartment phones of Washington Post reporter Gray Grantham, but knows better than to try to infiltrate the newspaper's offices. Barr is sent to the Caribbean to learn the truth from Victor Mattiece. The trip with blacked out windows and massive guards causes Barr to curse Coal and want to abandon the mission, but he reminds himself of his training and skill. Barr learns the truth, but does not live to bring the information home. He is killed in the same fashion as Justice Jensen, his neck broken and strangled