There are many differences between a criminal CP prosecution and a civil case involving allegations of copyright violation. I don't know enough about it all to get into the (significant) procedural differences, or the ways in which standards of evidence vary between criminal and civil cases, but I will note one fact that I think is significant here: Possession of CP is a "strict liability" crime, while copyright infringement is not.
From that one fact flows most of the substantive difference between criminal CP possession/creation/distribution cases and civil intellectual property claims, it seems to me. CP itself is patently illegal, as well as patently illegal to possess
no matter how you ended up in possession of it. Thankfully for ALL of us, copyrighted materials are not automatically illegal to have in your possession. Sure, the
means by which you obtained a digital copy of any given movie or song that is subject to copyright could be illegal, but there's nothing patently illegal about the movie/song itself.
I also suspect it makes a big difference to the court in these copyright cases whether the plaintiff(s) appear to have any intent to actually litigate their claims. In the cases that Judge Brown was ruling and commenting on, it appears that he has not been persuaded that the plaintiffs intend to litigate; he thinks they are just fishing for the identity of people that they can enter into settlement negotiations with, and have no real intent to follow through with a lawsuit against any who do not settle.
Whether or not he's sympathetic to the plaintiffs' claims or the plight of their businesses that stems from widespread pirating of their content, a judge has to consider the court's interests, as well. At the end of the day, the court really isn't supposed to be merely a means by which plaintiffs can secure a list of possible defendants to pressure into settlements -- particularly if the court gets the sense that the plaintiff's plan does not include litigation, at all, and that the whole point of lumping defendants together in a single complaint is to avoid paying the court $350 per filing to go after each defendant individually.
I think it's pretty easy to see where Judge Brown is coming from, at least from the court's perspective. He isn't completely against porn companies enforcing their copyrights; he just wants to see it done in ways that are consistent with the rules of civil procedure, the federal rules of evidence, and that respect the court's purpose and protocols. That's why he is severing all but one John Doe in the Malibu Media cases, but allowing the cases to proceed against "John Doe #1," and dismissing the other defendants without prejudice, which enables Malibu to refile against those defendants (albeit one at a time) in the future
