be a moot point

be a moot point

To be a topic that can no longer be questioned or debated. Whether or not he's the best person for the job is a moot point now that he's tenured.
See also: moot, point
Farlex Dictionary of Idioms.

be a moot ˈpoint/ˈquestion

be a subject that people disagree on or are uncertain about: It’s a moot point whether women or men make better drivers.A moot was a group of people who met to discuss questions of local or national law during the Anglo-Saxon period. A moot point was a question of law discussed at this meeting.
See also: moot, point, question
Farlex Partner Idioms Dictionary
See also:
  • be a moot point/question
  • moot
  • be a moot question
  • be going great guns
  • if (one) is a day
  • if he is a day
  • if he's, she's, etc. a day
  • sex on a stick
  • sex on legs
  • at heart