Abstract This chapter examines one of the key objections to admitting character evidence: that it is prejudicial. It also explains the concept of comparative propensity, which is used as the basis to explain the relevance and probative value of character evidence. Experimental studies provide little evidence that bad character evidence is prejudicial. While previous convictions for a similar crime do affect ratings of guilt and verdicts, the impact is generally moderate and not out of line with the probative value of criminal record. The data on real trials suggest that jurors will work out whether a defendant has previous convictions and therefore that evidential rules excluding such evidence have little impact.