A persistent conjecture regarding the potential problems in the clinical use of hair assays has been that drug concentration in hair may have a racial bias. In sociocultural terms, “bias” has a negative connotation and inherently implies a value judgment. In this controversy, however, the racial bias criticism seems to be directed at what one might call a “technical bias.” In statistical use, the concept “bias” indicates a systematic departure from the random occurrence of an empirical property in any particular sample. Sociological bias becomes an issue when some consequence is attached to the empirical differentiation. Thus the “bias issue” in hair testing is a cultural one, because illegal drug use is generally considered “negative” in contemporary society and in the law. In some circumstances, the data’s statistical treatment does not lend support to either a racial or a hair color bias.