The Prison Population Forecaster – Ryan King, Bryce Peterson, Brian Elderbroom, and Elizabeth Pelletier – “Roughly 2.2 million people are locked up in prison or jail; 7 million are under correctional control, which includes parole and probation; and more than $80 billion is spent on corrections every year. Research has shown that policy changes over the past four decades have put more people in prison and kept them there longer, leading to exponential growth in the prison population even while crime has dropped to historic lows. But despite widespread agreement that mass incarceration is a serious problem, the national conversation is light on details about what it will take to achieve meaningful and sustainable reductions. What do states actually need to do roll back their prison populations by 10 percent? 20 percent? 50 percent?…”