Utah's federal court has revamped its rule concerning sentencing of prisoners, a change prompted by legislation passed last year that set up new sentencing guidelines.

Some parts of the new rule have already been in effect informally, a court expert said.Because the change is a result of the legislation and not the sentencing guidelines themselves, it won't be affected by a challenge to the constitutionality of the guidelines. The legal challenge was launched by G. Fred Metos, lawyer for John Timothy Singer, one of the Singer-Swapp defendants.

Under the guidelines, points are given for such things as the nature of the offense, type or lack of prior rec-ord and severity of the crime. Some defense lawyers say the points reduce a judge's flexibility, and at least two federal judges have ruled the guidelines unconstitutional.

A hearing on the constitutionality of the guidelines is set for 4 p.m. June 17. Utah's federal judges will sit as a panel to hear the challenge.

In the new rule, a court expert said, one of the most important changes is the requirement that judges and magistrates will schedule sentencing for no earlier than 60 days after a conviction, either by plea or verdict.

According to the new requirement, called Local Criminal Rule 113, a pre-sentence report - including computation of points under the new guidelines - will be completed and given to both defense and prosecution within 35 days after the defendant is found guilty. The pre-sentence report is prepared by federal probation officers to help guide the judge.

"If the court, after consultation with the U.S. Probation Office, determines that the 35 days provided the Probation Office for the investigation and compilation of the pre-sentence report can be expedited, the court may reduce the 60-day period accordingly," the new rule says.

The 60-day period can also be reduced if the defendant wishes it to be reduced, and he "does not dispute the sentencing factors or facts material to sentencing contained in the pre-sentence report."

The order changing the rule is signed by U.S. District Chief Judge Bruce S. Jenkins, District Judges David K. Winder, J. Thomas Greene and David Sam and Senior Judge Aldon J. Anderson.