The latter half of this century has seen an erosion in the perceived legitimacy of science as an impartial means of finding truth. Many research topics are the subject of highly politicized dispute; indeed, the objectivity of the entire discipline of psychology has been called into question. This essay examines attempts to use science to study science: specifically, bias in the interpretation and use of empirical research findings. I examine theory and research on a range of cognitive and motivational mechanisms for bias. Interestingly, not all biases are normatively proscribed; biased interpretations are defensible under some conditions, so long as those conditions are made explicit. I consider a variety of potentially corrective mechanisms, evaluate prospects for collective rationality, and compare inquisitorial and adversarial models of science.