Here are three sources I recently came across that do a great job at visually representing the trends of incarceration across the country and around the globe.
1. Many Eyes, US Prison population by state (thanks to M. Thomas for the link). This shows the dominance of incarcerated populations by state from 1990 to today. I wish they had similar graphics going all the way back to colonial times.
2. Google Earth prisons around the world (download here). Need help visually understanding where the most prisons in the world are what countries operate them. Check out Ireland, the UK, California, and Texas. Once again I would live a full time series from the dawn of civilization till modern times that shows the facilities cropping up like this.
3. The global prison population by country. Not as visual as the previous two but thorough. I’m thinking of running a quick regression against the economic freedom index. Any suggestions?