Admissibility of a Witness's Mental Health History for Purposes of Impeachment

• Publication year: 1992
• Pages: 1405

21 Colo.Law. 1405 Colorado Lawyer 1992.

1992, July, Pg. 1405. Admissibility of a Witness's Mental Health History for Purposes of Impeachment

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1405

Vol. 21, No. 7, Pg. 1405

Admissibility of a Witness's Mental Health History for Purposes of Impeachment

by Mark E. Saliman and Katherine A. Cvengros

Q: Is evidence of a witness's past or present mental health or mental health treatment admissible pursuant to Rule 607 of the Colorado and Federal Rules of Evidence?

A: Yes, such evidence may be admissible to impeach a witness if the evidence is relevant to the witness's credibility.(fn1)

ASSUMED FACTS

In an employment discrimination case, the plaintiff calls a witness who was present during some of the alleged discriminatory incidents to bolster the plaintiff's version of the facts. During the deposition of this witness, counsel for the defendant employer learned that the witness has a history of treatment for mental and emotional illness. Defendant's counsel was unable to obtain the witness's medical records or speak with the treating psychologist, but was able to find several persons who can testify that the witness told them of his condition and of his treatment. Defendant's counsel believes that the witness misperceived the alleged discriminatory incidents, due to his mental condition.

Defendant's counsel wants to know whether, during cross-examination of this witness, he can question the witness regarding his mental health history, and whether he can introduce expert testimony showing that the witness's admitted mental health history would diminish his ability to recall, perceive or to communicate the incidents accurately.

DISCUSSION

The general rule under Rule 607 of the Colorado and Federal Rules of Evidence is that evidence of a past or present mental condition is admissible to impeach a witness if it is relevant to the witness's credibility,(fn2) because such evidence tends to show that the witness has a lessened ability to perceive, recall or accurately narrate the facts.

The seminal case allowing the introduction of this type of evidence is United States v. Hiss.(fn3) In the trial of Alger Hiss, the defense sought to introduce evidence regarding the mental condition of the government's primary witness, Whittaker Chambers, who allegedly had a psychopathic personality disposed to chronic lying. The court allowed the evidence, holding:

The existence of [a mental...