In this study, unwarranted disparity was defined as residual variation in sentence not attributable to legally mandated sentencing factors. The analysis showed that Minnesota's guidelines worked dramatically to reduce sentencing disparity for the prison length decision. They also curtailed disparity for the no prison/prison judicial decision, but to a lesser degree. The results also showed that sentencing equality diminished over time for the no prison/prison sentencing outcome. Possible explanations for this reversion are that many offenses, particularly assault in the second degree, did not warrant prison sentences, and that increases in sentencing inequality resulted from attempts to constrain the growth of the State's prison population. 1 table, 2 figures, 6 notes, and 19 references