Tempest (dimension-hopping supermage and father of two, with a CvK and an honor code at the Total level) would probably do something along these lines.
First, he'd stop by radio shack and pick up a camcorder. Then, since he's a bit of a luddite, he'd have the team's gadgeteer show him how to work it. Then, he'd wait outside our friendly neighborhood sex offender's house with said camcorder for him to get started again. He'd start recording right after the small child appears, and stop recording right before the small child is dismissed.
Then, armed with this evidence, he'd march to various experts in digital video recording, electronics, and magic (preferably parents themselves) and have them sign affidavits that the tape wasn't tampered with in any way. Then, after a brief lecture along the lines of "whatever you do, don't go to this guy's house (which happens to be at X address) and beat him up; let the police handle it," I'd call my contact in the L.A.P.D. and arrange to drop off my evidence. I'd make sure to give him the suspected felon's address, as well as inform him that the perpetrator seemed to have some non-combat-effective superpowers and that I'd spoken with the child in question and he didn't seem to remember anything.
Then, in compliance with local laws, I'd go to each of his neighbors' houses and inform whoever was there that their neighbor is a suspected child molester, and that while he did seem to have some superpowers, they weren't combat effective, so they didn't have to worry about, for example, fire blasts or anything. I'd stress to them that nothing has been proven yet, and that it may take a while for formal charges to be brought, since his alleged victims didn't seem to remember a thing.
Then, after a few days, if he was still alive, I'd leak the story to the press. Tempest has been around a long time, and he knows very well that human nature can be a sword and shield if need be.
Of course, all this would be moot if Tempest didn't see him first. Our team consists of a highly moral yet strangely pragmatic bowman with +10 telescopic vision, find weakness 15-(or thereabouts), and a 3d6+1 penetrating RKA, a streetwise ex-con who's made no bones about using deadly force when he feels it's necessary (he's packing a chainsaw right now in anticipation of a rematch with one particularly nasty villain), a hot-tempered brick and the high-kicking, overprotective mother of his two children, an ex-counterterrorist espionage operative with lots of unsavory connections and an 8 year old son, another ex-spy who hates men anyway, and a few others who'd come along and bring popcorn. Come to think of it, in my team, I'm probably in the minority in not kicking this guy's butt myself.
Oh, and for what it's worth, your GM has issues for springing this on you. Seriously.
Hope this helps,
-grump