The U.S. may have the world’s most complex sentencing system, says Governing. Along with the vast number of criminal offenses (there were 4,450 federal crimes as of 2008), there’s an array of rules and exceptions that impact a defendant's sentence. These include the severity of the crime, the number of offenses committed, credits for time already served, and the defendant's criminal history. Errors occur. In 2014, corrections officials in Nebraska discovered they used a flawed formula and miscalculated mandatory minimum sentences for more than 700 inmates, leading to the premature release of nearly 200 prisoners. The state estimates it will cost $10 million to re-incarcerate the prisoners who were released prematurely. In Colorado, a 2013 audit said the state incorrectly sentenced as many as 1,000 inmates.
To help deal with the complexity of calculating prison sentences, a few states are turning to technology. Minnesota developed a software calculator for probation officers to use. Nathaniel Reitz of the Minnesota Sentencing Guidelines Commission says probation officers calculate sentences using a worksheet that incorporates the commission’s guidelines. Michigan, with a prison population of 40,000 and another 60,000 on parole, was using a mainframe computer program to crunch the numbers. In 2013, the state ditched its legacy program and began installing a state-of-the-art software system that can sort through 200 sentencing rules and 5,000 combinations involving as many as 12,000 calculations on a daily basis. The program can juggle sentences that are reduced by credit for time served, good behavior and participation in prison work or education programs. It can extend sentences for things like bad behavior and refusal to take drug or alcohol tests.