Following through after 'outing' seems a non-solution; you could still start cases you know you have a small (if any) chance of winning to 'out' someone.
My initial reaction actually was people cannot and should not expect anonymity on the internet, unless extreme measures are taken which often still do not guarantee anonymity 100%. Furthermore, it is not something people should want; if crimes are committed via internet or with assistance of it, then through proper procedures law-enforcement should be able to track culprits.
This however was not the case here, and so far I can see the only 'solution' would be to keep the identity of the accused anonymous during the trial and make it known only after a guilty verdict. This won't work, however, since often the daily life of the accused is relevant to the court proceedings; the accusing party has a right to be able to research what more the accused has been up to.
Perhaps an anonymous trial is only feasible for a small subset of charges. Don't see it happening though, this is probably just a necessary evil.
On a sidenote, if the charges are too ridiculous, any court would just dismiss the charges entirely without anyone being drawn out.