"[D]rug mandatory minimum penalties continue to have a significant impact on the sentencing of drug offenders and on the federal prison population. The data demonstrates that offenders convicted of an offense carrying a drug mandatory minimum penalty continue to receive longer sentences than offenders not convicted of an offense carrying a drug mandatory minimum. These longer sentences, coupled with the fact that drug offenses are the most common offenses carrying mandatory minimum penalties, considerably affect the prison population. At the end of the last fiscal year, nearly half of all federal inmates were drug offenders and nearly three-quarters of those drug offenders in prison were convicted of an offense carrying a drug mandatory minimum penalty. The data also demonstrates that the effects of mandatory minimum penalties on sentencing occur for drug offenders across the culpability spectrum and regardless of an offender’s role in the offense."