A powerful group of United States senators unveiled a bill last month designed to reform federal criminal sentencing laws. If passed, the Sentencing Reform and Corrections Act of 2015 will begin to address some of the most troubling areas of federal criminal sentencing – the cause, many experts say, of exponential growth in the federal prison population. The bill would reduce mandatory life sentences without parole for some drug offenses, allow parole for people sentenced to life for crimes they committed when juveniles and expand the number of inmates over 60 years old who can seek compassionate release from prison. It provides judges with greater discretion at sentencing for some drug crimes and allows for retroactive application of the 2010 federal law that reduced the unfair disparity in sentence lengths between crack and powder cocaine. The bill is particularly noteworthy for its bipartisan support, which includes Sen. Charles Grassley. The Judiciary Committee chairman has been a staunch supporter of harsh punishments, including mandatory minimum sentences, reflecting a hopeful trend that the uniquely American experience of …