One of the hardest things to imagine about our system of justice is how stringently the rules must be applied. In the U.S. criminal justice system, the defendants are considered innocent until the state can prove them guilty, and the burden of proof can be burdensome.

There are rules for gathering evidence, rules for handling evidence, rules for how the accused has to be handled or questioned or even if he can be questioned. If those rules are violated, a defendant, even one who is most certainly guilty, has to be set free.

So it with Bill Cosby, accused of drugging and raping Temple University Andrea Constand. The evidence presented at his trial made it clear that Cosby had done what he was accused of doing. However, part of that evidence was incriminating statements he had made in a civil trial brought by Constand, statements he had made with the promise by the prosecutor at the time that he would not face criminal charges.

Later on, a different prosecutor decided he should not be bound by the earlier promise and charged Cosby anyway. The Pennsylvania Supreme Court ruled this week that the second prosecutor was indeed bound by the first one’s promise, and it overturned the conviction.

So this is how the justice system works. Cosby’s conviction is overturned, even though the facts about what he did remain. He is not guilty, though hardly innocent. It is a hard pill for the #MeToo movement to swallow, but that is the way the justice system works.