Research and theory on the effects of fair procedures has gained popularity over the past decade. This is understandable given the inherent appeal of these ideas and the supporting evidence. Research suggests that authorities are able to secure compliance from subordinates when they use fair procedures and when they are viewed as legitimate. Unfortunately, empirical studies of procedural justice and legitimacy are hampered by weak measures of key theoretical constructs. The purpose of this study is to examine the measurement properties of procedural justice in a sample of inmates. Results show that a one-factor model of procedural justice fits the data well, though the authors find evidence of a method effect. Results also demonstrate important differences between the use of a summated procedural justice scale and a scale derived from a factor analysis. These findings illustrate the importance of paying careful attention to construct validity in measures of procedural justice.