In addition, the State has not experienced any widespread efforts to undermine the legislation by administrative tactics or any adverse effects on trial court efficiency or the prison population. The law set standard prison terms for each felony committed on or after July 1, 1981, and required judges either to impose the standard term or to give written reasons for imposing a different term. The study of the law's impact used data from interviews with prosecutors, judges, and defense attorneys and from a sample of over 2,500 cases handled in 12 districts either before or after the law's implementation. It also used over 15,000 cases in the Department of Correction statewide felony sentence sample; data on over 3,200 felons released from prison between 1978 and 1981; and data on 1,457 felony judgments issued under the law between August 1981 and January 1982. A decline in the number of felony charges per defendant was found, from 1.90 to 1.56. Jury trials dropped from 5.7 percent of all defendants' dispositions to 3.2 percent. The rate of guilty pleas remained almost constant at almost 60 percent. Trial court disposition times decreased, but not necessarily because of the law. Over half the defendants convicted received standard prison terms; 22 percent received sentences resulting from plea bargains; and judges gave written reasons supporting sentences in only 17 percent of cases. Sentencing variations decreased, and sentencing became gradually less severe. The effects of some variables on the sentence changed after the law's passage. Prison populations were not adversely impacted because the greater likelihood of a prison sentence was counterbalanced by shorter sentences. In its first year, the law has brought changes in the desired directions. Fifteen footnotes, a table, and a figure are included.