A prison and sentencing impact assessment is the Commission's appraisal of the impact that changes to the sentencing guidelines or criminal statutes will have on the federal prison population. Commission staff collects data from documents sent by the courts for each case in which a defendant is sentenced. From that data, a database is created that includes information on guideline application, statutory penalties, and sentences. Commission staff analyzes information from this database to estimate the possible prison and sentencing impact of proposed legislation that may affect criminal statutes and the federal sentencing guidelines.