On December 15, 2011, the Institute of Medicine (IOM) Committee on the Use of Chimpanzees in Biomedical and Behavioral Research issued a final report commissioned by the National Institutes of Health (NIH). It changed the landscape of discussion about the necessity of using chimpanzees in research. The Committee advanced three principles of scientifically warranted research on chimpanzees, but NIH’s statement of task provided inadequate opportunity for the Committee to investigate moral problems and their implications for public policy. The IOM Committee’s report is a landmark document, but it has weaknesses in its justificatory framework, largely resulting from the Committee’s narrow remit from NIH and IOM. We analyze cases mentioned in the report and argue that numerous central ethical issues are neglected, especially ones of justification. Additionally, we consider whether the principles offered by the Committee could be used as criteria governing the use of other animals in biomedical and behavioral research.