Below is a link to a presentation by Chief Research Officer Mark H. Allenbaugh.  In the in-depth presentation he provides a statistical overview of how the sentencing landscape has changed under the U.S. Sentencing Guidelines over the past 30 years.  He notes how increased prosecution rates and average sentences have contributed to the explosion in the federal prison population, and proposals for fostering the recent downward trend in population.  Finally, he encourages Congress and the U.S. Sentencing Commission to develop legislation and Guidelines to encourage judges to more frequently utilize alternatives to incarceration–most prominently probation–as a means to combat over-incarceration and bring the sometimes unduly severe sentencing guidelines into check.