John Pfaff wrote a piece for Slate that dispelled myths about prison growth.
Myth No. 1: Long sentences drive prison population growth. The stories that capture our attention are the low-level crooks who get 25 years for stealing three $400 golf clubs. But these cases get a lot of press precisely because they are exceptional.
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Myth No. 2: Low-level drug offenders drive prison population growth. It is popular, perhaps almost mandatory, to blame the boom on the War on Drugs. But it is just not true.
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Myth No. 3: Technical parole and probation violations drive prison population growth. Recent advances in drug testing and other forms of monitoring have sparked concern that we are sending more and more parolees back to prison for minor infractions. And as with all the factors discussed here, there is a kernel of truth to this one.
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Myth No. 4: In the past three decades, we’ve newly diverged from the rest of the world on punishment. Given that our incarceration rate before the mid-1970s is one-seventh the rate of today, it is easy to think that we’re suddenly acting like outliers. But the fact is that American views on punishment have been harsher than Europe’s since the birth of this country (although politicians may overestimate the extent to which they must be tough on crime to win elections).
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Myth No. 5: The incarceration boom has had no effect on crime levels. Sometimes, crime rates have fallen as the prison population has risen (the 1990s and 2000s) or risen as the population fell (the 1960s). At other times, however, the crime rate has risen even as the prison population also rose (the 1970s and ’80s).