Research ethics committees ‘(RECs) members’ perceptions of their role in regard to the science of research proposals are discussed. Our study, which involved the interviewing of 20 participants from amongst the UK’s independent (Phase I) ethics committees, revealed that the members consider that it is the role of the REC to examine and approve the scientific adequacy of the research – and this notwithstanding the fact that a more competent body will already have done this and even when that other (...) body has the legal responsibility for this function. The problematic nature of this situation, tantamount to double jeopardy, is considered: it can delay research and so add to costs whilst offering no countervailing benefits, or the double jeopardy may be just the cost society imposes, through its RECs, on researchers as the price for research on human subjects. (shrink)