15.15 - C. Bias, Interest, Motive, Corruption, Hostility

• Jurisdiction: New York

C. Bias, Interest, Motive, Corruption, Hostility

A witness’s bias, interest, motive, corruption or hostility can always be brought out by the cross-examiner.²¹¹⁶ The fact that the witness has an unrelated criminal or civil claim against the defendant, or contemplates a suit against the defendant for injuries arising out of the criminal activity that is the subject of the trial, is fair game in a cross-examination of that witness.²¹¹⁷ Favorable treatment and evidence that is probative of motive to lie is not collateral.²¹¹⁸ Bias may also be shown by evidence of a family, business or close relationship, or by acts or declarations of the witness. The hostility of the witness to the person against whom he testifies may be shown by his own admission while on the stand in answer to a direct question as to his attitude toward one of the parties or by proving the witness’s hostile acts or declarations through his own testimony or by the testimony of others.²¹¹⁹ It is proper to embody, in a question seeking the personal feelings of a witness, a further query as to the cause or causes upon which these feelings are predicated.²¹²⁰

It is not necessary to lay a foundation to demonstrate bias, interest or hostility by first calling the attention of the witness to the act or declaration. It may be proved by any competent evidence.²¹²¹ It may be shown by cross-examining the witness, or witnesses may be called who can swear to facts showing it. The extent to which an examination may go for the purpose of showing bias, interest or hostility of a witness is, to a large degree, within the discretion of the trial judge.²¹²²

The following sections contain illustrative cross-examinations of various types of witnesses.

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