Research on incompetent humans raises ethical challenges, especially when there is no direct benefit to these research subjects. Contemporary codes of research ethics typically require that such research must specifically serve to benefit the population to which the research subjects belong. The article critically examines this "same-population condition", raising issues of both interpretation and moral justification. Of particular concern is the risk that the way in which the condition is articulated and rationalized in effect disguises or downplays the instrumentalization of incompetent individuals.