Selection of an appropriate sentence is one of the most important decisions to be made in the criminal justice system. The primary vehicle to assist the sentencing court in fulfilling this responsibility is the presentence investigation report.

As community corrections professionals, probation officers preparing presentence investigation reports possess and use skills from various disciplines to investigate relevant facts about defendants; assess those facts in light of the purposes of sentencing; apply the appropriate guidelines, statutes, and rules to the available facts; and provide accurate, timely, and objective reports that will assist the sentencing judges in determining appropriate sentences, aid the Bureau of Prisons in making classification, designation and programming decisions, and assist the probation officer during supervision of the offender in the community.

The probation officer's role as the court's independent investigator is crucial, although the scope of any investigation may be modified by the court. Probation officers may receive information from all parties, but are cautious about adopting any party's interpretation outright. It is the probation officer's responsibility to prepare all sections of the presentence report, including the advisory guideline range. Attorneys for opposing sides may aggressively contest the accuracy of facts contained in the presentence report or application of the guidelines to those facts. Probation officers are prepared to respond to these situations professionally by having all supporting documentation readily at hand. Throughout the investigation, the probation officers treat the defendant, the attorneys and others with dignity and respect. The probation officer's objectivity and professionalism during the presentence and sentencing phases promote the fair treatment of the defendant, and may instill in the defendant the desire to cooperate with corrections and community corrections officials in the latter phases of the federal criminal justice system.