# lone gunman

idiom

Source: https://englishreference.com/idiom/lone-gunman
Updated: 2026-08-10

## Meaning

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.

## Examples

- The police suspect a lone gunman committed the crime.
- He plays the lone gunman role at work by making every decision himself.
- Investigators initially searched for a group of suspects, but evidence soon suggested the act was the work of a lone gunman.
- The manager acted as a lone gunman when he fired the staff without consulting the rest of the board members.
- I do not want to be a lone gunman in this project because I need a team to share the responsibility.
- Historians continue to debate whether the tragic event was a coordinated conspiracy or the isolated action of a lone gunman acting entirely on his own accord.

## Origin

From the Warren Commission's lone gunman theory, that the assassination of U.S. President John F. Kennedy was the work of a single individual, subsequently applied to numerous other political assassinations and shootings.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.