Dateline: June, 2007, Issue 1
Character witnesses offer general positive information about a defendant's personality and good character, and can be impeached through cross-examination that allows prosecutors to introduce specific bad acts in which a defendant has engaged.
Recent research by Hunt and Budesheim (2004) studied the effects of positive character evidence when offered alone, and when followed by a prosecutor cross-examining about specific bad acts.
These researchers found that, on its own, general descriptions of a defendant's positive personality characteristics had little effect on juror decision-making; that is, positive character evidence did not reduce guilt perceptions or decisions to convict. Additionally, when a character witness was cross-examined with examples of a defendant's previous specific bad acts, jurors' impressions of the defendant were more negative, guilt perceptions higher, and conviction decisions more likely than when no information at all was provided about the defendant's character.
The researchers concluded that permissible positive character evidence does little to help a defendant, and negative character evidence in the form of specific bad acts cross-examination can hurt a defendant considerably.
Source Hunt, J. S. & Budesheim, T. L. (2004). How jurors use and misuse character evidence. Journal of Applied Psychology, 2, pp. 347-361.