Colo. R. Evid. 607
The credibility of a witness may be attacked by any party, including the party calling him. Leading questions may be used for the purpose of attacking such credibility.
CRE 607
Committee Comment
This rule abandons the traditional position against impeaching one's own witness. The additional sentence in the Colorado version of the rule should assist in resolving conflicts now existing between Rule 43(b) of the Colorado Rules of Civil Procedure and § 13-90-116 , C.R.S. A minority opinion concerning Rule 607 feels that this rule should be restricted to civil cases since it may be prosecutorial misconduct for a prosecutor to attack the credibility of his own witness without a showing of hostility or surprise. The likelihood of a defendant's being found guilty because of a "coparticipant" hesitation to testify against the defendant may prejudice the jury to such an extent that a fair trial cannot be obtained.
Annotation Law reviews. For article, "Admissibility of a Witness's Mental Health History for Purposes of Impeachment", see 21 Colo. Law. 1405 (1992). For article, "Impeachment", see 22 Colo. Law. 1207 (1993).