Well, in the Swedish case where TPB had issues with the judge, the judge was chosen essentially because they knew what this newfangled filesharing thing was, which was more than could be said for just any random judge.
That makes a lot of sense; guess that's it. But I would say it's duty of the gov to make sure every expertise significantly large has at least 2 judges capable. Otherwise it's too easy to get into this kind of weirdness.