"As previously noted, various drug offenses carry a mandatory minimum. For such offenses, the mandatory minimum precludes judges from sentencing at a lower guideline range minimum or from granting a downward departure that might otherwise be available, unless one of two statutory provisions applies. First, a judge may impose a sentence below the applicable mandatory minimum if the government (the federal prosecutor) files a motion with the court for such sentencing relief because of the defendant's 'substantial assistance' in the investigation or prosecution of another person. The discretion to make such a motion rests solely with the prosecutor. Second, in the absence of a substantial assistance motion, the 'safety valve' provision affords relief from any otherwise applicable mandatory minimum sentence for drug offenders who have minimal criminal history (i.e., no more than 1 criminal history point); were not violent, armed, or high-level participants; and provided the government with truthful information regarding the offense. In these cases, the court is directed by statute to impose a sentence pursuant to the sentencing guidelines without regard to a mandatory minimum."


General Accounting Office, "Federal Drug Offenses: Departures from Sentencing Guidelines and Mandatory Minimum Sentences, Fiscal Years 1999-2001," (Washington, DC: October 2003) GAO-04-105, p. 9-10.