WASHINGTON -- Last month, The Huffington Post surveyed the major 2016 presidential candidates in an effort to compare their views on criminal justice. The two leading Democratic contenders, former Secretary of State Hillary Clinton and Vermont Sen. Bernie Sanders, participated -- as did former Maryland Gov. Martin O'Malley, who has since suspended his campaign following a poor showing in Iowa.

Here's what we learned . The Democratic presidential nominee -- whether Clinton or Sanders -- will call for expanding federal investigations into local police departments, believe racial inequalities in the criminal justice system cannot be explained away by economic disparities, and think a variety of factors -- not mass incarceration alone -- contributed to the historically low levels of violent crime in the U.S. in recent years.

The nominee will also think that prisons need to put more emphasis on rehabilitation, that the harmful practice of solitary confinement should not be used as a punishment, and that the U.S. Department of Justice should dole out federal grants in ways that push law enforcement agencies across the country to stop routinely violating constitutional rights.