Pretrial occurs after an individual has been arrested until the adjudication of their federal case. A pretrial services officer gathers information about the defendant through interviews and record checks to prepare a report for the judge. The judge determines if the defendant can be released or should be detained.

If the defendant is granted pretrial release, the pretrial services officer will supervise according to their conditions of release. The goal is to reduce any danger to the community, follow the conditions of release, and attend required court hearings.

A probation officer begins a presentence investigation if a defendant is found or pleads guilty. If the defendant receives a custody sentence, the pretrial services officer typically continues supervising the defendant until their report date. If a probation sentence is ordered, post-conviction supervision begins. Pretrial supervision can last from a few months to several years.