The analysis, done by the Vera Institute of Justice, finds that in 2014 and 2015, 46 states passed 201 bills, executive orders and ballot initiatives.
Those reforms ranged from improving bail systems to supporting recently released former prisoners.
Other fixes curb the use of solitary confinement.
Some states created specialty courts for veterans, the homeless and drug addicts.
Nationwide, lawmakers are trying to reduce the number of people who ended up behind bars by shortening jail stays and providing alternative sentences.
Tonya J. Powers, FOX News.