A pre-sentencing investigation, or PSI, helps the judge determine whether a person convicted of a crime goes to jail or is allowed to remain free on probation. It contains information about the convicted person, the case and the victim's experience and plays a significant role in the sentencing decision.
The pre-sentencing investigation has been a major part of the American criminal justice system since the 1920s. It evolved from a long social tradition of believing that a person committed a crime for reasons unique to that person, and that the underlying motivation for crime could be treated on an individual basis, according to the Center on Criminal and Juvenile Justice. The PSI gives a judge a thorough background of an individual and is meant to guide sentencing and treatment for that specific person.
A PSI is used in different cases and situations according to state laws, which vary. Federal law requires a PSI only in death penalty cases. They are almost always conducted by a court system's probation or court services department. However, a defendant's lawyer sometimes commissions a "defense based" report for the case, since PSIs have been criticized for being biased against the defendant.
According to the Michigan State Appellate Defender's Office, the pre-sentencing investigation includes a wide range of personal and professional background information about the convicted person. It includes information on the person's finances, criminal history, marital history, education, medical history and substance abuse history. Information is gathered from documents and through interviews with the defendant's family.
Information from the victim in the case is frequently included in the PSI. The report can use police documents to explain harm suffered by the victim. The victim also can offer an impact statement for the PSI. In the impact statement, the victim describes from a personal perspective, the experience of the crime and its aftermath.