Lone Gunman Meaning

(idiomatic) An individual person who acts on his or her own initiative, without partners, especially one who has sole responsibility for doing something questionable, confidential, or iniquitous.

Example: 2002, Jed Mercurio, Bodies, ISBN 9780224061971, p. 340:
  He continues, "So when someone blows the whistle, the hospital has to start looking for a scapegoat. The hospital looks for the lone gunman—the individual, acting alone, acting counter to his training, who, through a gross act of incompetence . . . ."
2008, John Grisham, The Appeal, ISBN 9780440244974, pp. 197-198:
  Trial lawyers, always a colorful and eclectic bunch. . . . Most were lone gunmen too eccentric to keep much of a staff.
2008, Lee Raffel, I Hate Conflict! Seven Steps to Resolving Differences with Anyone in Your Life, ISBN 9780071484893, p. 260:
  The Wilson family had been sorely conflicted because each member had gone off in his or her own direction, thinking that they were all lone gunmen.