What is want of competency or legal fitness; incapacity; disqualification, as of a person to be heard as a witness, or to act as a juror, or of a judge to try a cause called?

incompetence — (Law) Want of competency or legal fitness; incapacity; disqualification, as of a person to be heard as a witness, or to act as a juror, or of a judge to try a cause. (Webster's 1913.)

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