That trend, however, lagged a similar increase in violent crime. Violent crime increased by a factor of five from 1962 to 1992: http://www.newgeography.com/files/cox-crime-3.png.
The causation seems to run in the direction of more crime leading to more incarceration. Incarceration rates stayed stable in the 1960s and early 1970s. By the time incarceration started ticking up in the early 1970s, violent crime had already increased by 2.5x. By 1980, the incarceration rate was about 40% higher than in 1960. But violent crime had increased by a factor of 4. The increase in incarceration rate didn’t catch up to the increase in violent crime rate until the mid to late 1990s, when violent crime started edging down.
I’m extremely sympathetic to the idea that criminal justice reform is required now that crime rates have gone down dramatically. But we need to grapple with our own history and the nature of our society. We went through a very violent phase from 1960 to 2000. We don’t know why that happened. But it seems pretty clear that our incarceration rate was a lagging response to that phenomenon.
Moreover, the overall increase in violent crime tracked the homicide rate. Homicides are very well reported, throughout the modern era. The homicide rate doubled from 1963 to 1973. That almost certainly reflects an actual increase in homicides, or just previously unreported homicides being reported due to increased policing.
Don't just bury the lede. What changed in the early 70s that would have caused such a thing.
> We don’t know why that happened. But it seems pretty clear that our incarceration rate was a lagging response to that phenomenon.
Yes, we do know what happened. The 70s saw Vietnam Vets coming back from a pointless war with PTSD and heroin addictions. Nixon signed the Comprehensive Drug Abuse Act in 1970. Reagan threw gas on the smouldering fire with the Comprehensive Crime Act and bang, everything is illegal and now with the mandatory minimum sentencing. At every opportunity the federal government, rather than evaluating to see if these laws were effective, chose to make more things criminal. This didn't dissuage gangs from engaging in illegal activity. It actually made them more paranoid and more violent. Anynone that might have been remotely considered a snitch or narc was killed. If you're staring down a life sentence if you got caught might as well remove any doubt.
Vietnam is one possible explanation, having started in 1955. I have never seen any analysis of that. But unlike the drug war, at least the timing works out.
I half suspect that long-term declining fertility rates is one reason we currently have such historically low rates of violence.