My first thought when I read this horrible news was this: There is a sin I would not want to have to explain to God on judgement day. Seriously. "Hi God, um... remember that time when I bore false witness against a priest who had helped people around the world with his direct, straight forward explanations of the faith? Yeah... I was just... um... kidding?"
Sex abuse is horrible. Yet in a different way, these types of lies, both against clergy and against lay people (often times men who have tried to help their communities and made enemies) can be just as damaging and traumatic. Lives are destroyed. Reputations are lost. Cases drag on for years and years and then, after being dragged through the mud the accused is acquitted with a whisper. After all, an acquittal doesn't quite get the same ratings that some drug addled woman ranting about sex or harassment gets.
Anyone can say anything. And in a society where a premium is placed on getting what we want, instead of doing what is right, telling a little lie for money, or attention or to hurt someone in a position of power that we've decided we don't like, may not seem all that bad anymore.
I'm sure Satan attacked this particular priest from every angle. After all, he's a man who has strengthened the faith and understanding of many. When that didn't work Satan decided on the next best thing: an attempt to discredit his work and all the good that he has done by leading someone weaker into sin.
We should pray for all involved. Maybe Saint Gerard Majella is a good patron saint for this case. He was falsely accused (google him to see how he became the patron saint of expectant mothers) and the woman who accused him finally repented and told the truth. What a sad day...