Many people think the justice system should systematically err towards mercy. Highway cops might have discretion to let people off with a warning for minor vio

Many people think the justice system should systematically err towards mercy. Highway cops might have discretion to let people off with a warning for minor violations, but the same discretion isn't supposed to let them punish people who are innocent. State governors have the power to grant pardons, but don't have the inverse power. And so on.