Prior to this position, Knight briefly worked as a police officer before he joined the United States Secret Service as a special agent in 1950.

[1] While the Great Depression in Canada was occurring, Knight spent part of his childhood living in Detroit, Michigan, with his family.

[11] In 1958, Knight protected the Vice President of the United States when an attack on Richard Nixon's motorcade occurred in Venezuela.

[12] In leadership roles, Knight continued to keep the vice president of the United States safe as a special agent in charge from 1961 to 1963.

[17][2][9] Knight was in charge of planning protection for Richard Nixon when he was to visit the Middle East as the United States president during 1974.

[18] The following year, Knight was the director of the Secret Service when assassination attempts were made on Gerald Ford in Sacramento and San Francisco during 1975.

[21] The following year, Knight continued to hold his director position when the attempted assassination of Ronald Reagan occurred in March 1981.

[26] Following the 1958 attack on Nixon, Knight was a recipient of the "exceptional civilian service award" from the United States Department of the Treasury.

[27] In 1987, Knight went to Murray State University to present the Harry Lee Waterfield Distinguished Lecture in Public Affairs.