Does suggestive information cause a confirmation bias in bullet comparisons?

Several researchers have argued that the confirmation bias, the tendency to selectively gather and process information such that it fits existing beliefs, is a main threat to objective forensic examinations. The goal of the present study was to empirically investigate whether examiners making bullet comparisons are indeed vulnerable to this bias. In the first experiment, six qualified examiners evaluated 6 sets of bullets that were presented to them twice.