The judge often orders a pre-sentence investigation after the defendant has been found guilty or pleads guilty and requests probation. The purpose of the pre-sentence investigation is to look into the defendant´s background to see if he or she is likely to be a good candidate for probation.
The pre-sentence investigation is conducted by the probation office. The defendant meets with a probation officer who interviews the defendant regarding past criminal offenses, educational and family history, employment record and use of alcohol and drugs.
Sometimes tests are conducted to measure a defendant´s drug or alcohol use as in a case where the defendant is charged with Driving While Under the Influence of Alcohol (DUI).
The probation office prepares a report on this information along with a recommendation to the court as to whether the defendant would be a good candidate for probation. The judge studies this report prior to making a decision.