At common law persons convicted of heinous offenses were not competent as witnesses. In order to be totally disqualified the witness must have been convicted of a crime making him infamous. The infamous crimes consisted of treason, felony, and all forms of the crimen falsi. Just what crimen falsi includes is not entirely clear, but generally it comprehends all crimes which involve fraud or falsehood rendering the guilty party entirely untrustworthy, and injuriously affecting the administration of justice. The disqualification of a witness for infamy has been quite generally abolished by statute. In the state of Washington several statutes have been passed regulating this question.
Notes and Comments,
Conviction of Crime as Affecting the Credibility of a Witness in the State of Washington—Competency of Persons Convicted of Perjury to Testify in Civil and Criminal Proceedings,
Wash. L. & Rev.
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