Another article from the National Review is available at this link.
Notes from the book:
“Most Americans believe that a majority of those in prison are serving time for drug offenses, but the reality is that only about 200,000 of the 1.3 million people in state prisons—under 16%—fall under that heading. The proportion is only slightly higher if we also include the much smaller federal prison system."
“By contrast, more than half of all inmates in state prisons—over 700,000 people—have been convicted of violent crimes. For all the attention that the media have paid to people given drastic sentences for drug crimes, almost everyone in prison serving long terms has been convicted of a violent act, often a serious violent crime.”
The book also points out nearly all drug offenders in prison are there for trafficking, not possession.