After the second conviction for drunk driving within 5 years or the third conviction within 10 years, the law stipulates that the offender must be sentenced to a jail term of 30 days or more, without stay of sentence. Alternatively, 8 hours of community service can be substituted for each day of jail time reduced from the 30-day sentence. If there are mitigating circumstances, however, the prosecutor can ask the court to ignore the minimum sentence provision. The mandatory minimum sentence applies to crimes committed on or after August 1, 1988. The law also specifies that the Minnesota State Planning Agency should monitor the minimum sentence provisions' implementation and use. The agency has already determined that habitual drunk drivers are more likely to go to jail and to serve longer terms in jail under the new law. The law's most noticeable effect, however, is that repeat offenders are less likely to get jail sentences that are shorter than 30 days. The minimum sentence law has had only a modest effect on average sentence lengths for repeat offenders; average sentence length increased by about 10 percent in 1988, from 58 to 64 days. Some Minnesota counties have been slower than others in implementing the law, so there may be a further increased in jail sanctions for drunk drivers than reported in the initial evaluation. 4 figures.