Proctor was born in 1926 in Reform, Alabama. He began work for the Bureau in 1952, spending ten years in New York keeping an eye on Soviets working at the United Nations. In 1962, Proctor accepted a job as a resident agent in Meridian working under the supervision of the FBI's New Orleans office. His responsibilities included investigating crime on Indian reservations, interstate auto theft, tracking down interstate fugitives, and investigated alleged violations of civil rights laws. As part of his job, Proctor cultivated friendships with all types who might aid in his job, from bootleggers to local law enforcement officials, Klansmen, black leaders, and civil rights workers.
The day after the disappearance of Schwerner, Chaney, and Goodman, Proctor was told by his New Orleans superisor, Harry Maynor, to begin an investigation. Proctor spent that day travelling around Neshoba County conducting interviews with blacks living near the burned church in Longdale and Sheriff Rainey and Deputy Price in Philadelphia. At the time, Proctor saw no reason to doubt the stories of Rainey and Price. After finishing his interview with Price, the Deputy Sheriff patted him on the back and said, "Hell, John, let's have a drink." Later that night, Proctor teletyped to New Orleans his initial report that indicated there was no evidence of a violation of federal law.
The next day, June 23, 1964, Proctor was joined in Meridian by ten special agents newly assigned to the case, as well as by his New Orleans-based supervisor. Proctor received a tip from the superintendent of the Choctaw Reservation, who reported seeing a smoldering car in northest Neshoba County. While Proctor was searching in the vicinity of the site of what turned out to be the burned CORE station wagon, he was greeted by Joseph Sullivan, the FBI's Major Case Inspector.
Proctor's knowledge of the people and habits of Neshoba County residents made him the most productive of the FBI's agents assigned to the case. Proctor would stuff his pockets with candy before going on interviews, having discovered that kids could be a useful source of information even when their parents remained tight-lipped. He was at the earthen dam burial site on August 4, where he took photographs of the bodies that were introduced, with great effect, at the trial.
Most significant to the breaking of the case was Proctor's success, achieved after five increasingly tough interviews, in convincing Klan member and witness to the shooting, James Jordan, to turn state's evidence. Proctor played both bad cop and good cop effectively. At one point he told Jordan, "I'm going to see your ass in jail." He offered Jordan $3500 for his full story and promised to stage an arrest so that other Klan members would not suspect he had turned informant. Eventually it was when Proctor played his trump card, his knowledge of Jordan's secret Klan number (12), that Jordan decided that he would be better off being a witness than a defendant.
In addition to his role in the Mississippi Burning investigation, Proctor used his influence with local law enforement officials to prevent additional trouble. When Martin Luther King came to Philadelphia, Proctor told Sheriff Rainey, "Lawrence, we're going to have King here and nothing is going to happen."
Proctor retired from the FBI in 1978 to open his own detective agency in Meridian. When interviewed in 1989, the twenty-fifith anniversary of the killings, Proctor refused to be photographed and was reluctant to discuss his role in the Mississippi Burning investigation. "I'm not a hero," he said, "I did my job." Proctor said that most of the men he helped put away still respect him. If Wayne Roberts, the triggerman in the killings, "walked in right now, he'd come over and shake my hand." Proctor predicted that "Mississippi Burning," newly released at the time of his 1989 interview, was "going to be as popular around here as a turd in a punch bowl."