Although available empirical evidence suggests that Minnesota's Determinate Sentencing Law has had little effect on prison incarceration, it is still uncertain whether the sentencing guidelines affected jail use. A few recent studies imply that the guidelines have had a positive effect on jail incarceration rates. Accounts have pointed to preexisting trends, more severe sanctioning of repeat property offenders, and judicial concern with prison overcrowding as possible underlying causes of this observed increase. The authors found that the onset of the sentencing guidelines increased judicial use of the jail sanction beyond the effect of preexisting trends. In addition, the effect of mitigated dispositional departures from the no prison/prison outcome on jail use is salient only when prison populations are high. This latter finding supports the thesis that judicial concern with prison overcrowding motivated judges to circumvent the guidelines in order to shift the burden of incarcerating offenders from the State to the local level. The policy implications of these results for determinate sentencing reform are discussed. Footnotes, figures, table, references