The DA's office won't prosecute if they don't think they have a solid enough case. It's not whether they think he's guilty or not.
The innocent until proved guilty relates to his treatment. He can't be jailed for being presumed guilty without a trial to present enough evidence. He can be guilty as all get out and everyone can know it, but unless they can prove beyond a reasonable doubt with hard evidence in a court of law, there's nothing that can be done.
The problem is, the way Catholics demand it be handled would prohibit any law enforcement from ever being able to pursue a case against any criminal.
While one is innocent until proved guilty, people are allowed to THINK he's guilty. Police are allowed to infringe on his rights to a limited extent and bring him in for questioning and book him for reasonable suspicion. They are allowed to set bond or bail for him, all before the trial; all before being officially declared guilty so that a sentence can be passed.
So, as a technicality, he must be treated as innocent until proved guilty so that he is not jailed without just cause, but that doesn't mean people can't think he's guilty.
So, sounds like he's guilty to me and I'm going to think so.
Get over it.