  Compared with participants who were first shown pictures of white faces, those who were primed with black faces in Payne (2001) were faster to identify pictures of guns as guns and were more likely to misidentify pictures of tools as guns. This finding has been directly and conceptually replicated (e.g., Payne et al. 2002; Conrey et al. 2005) and is an instance of a broader set of findings about the effects of attitudes and beliefs on perception (e.g., Barrick et al. 2002; Proffitt 2006). Payne’s findings are chilling particularly in light of police shootings of unarmed black men in recent years, such as Amadou Diallo and Oscar Grant. The findings suggest that agents’ implicit associations between “black men” and “guns” may affect their judgment and behavior by affecting what they see. In addition to the moral implications, this may be cause for a particular kind of epistemic concern. As Siegel (2012, 2017, forthcoming) puts it, the worry is that implicit bias introduces a circular structure into belief formation. If an agent believes that black men are more likely than white men to have or use guns, and this belief causes the agent to more readily see ambiguous objects in the hands of black men as guns, then when the agent relies upon visual perception as evidence to confirm her beliefs, she will have moved in a vicious circle.