Yale Law Professor Jed Rubenfeld is representing Children's Health Defense, an anti-vaxx organization founded by Robert Kennedy JR., in its suit against Facebook for slapping "content warnings" on their material, which spreads false conspiracies about vaccines in general and the COVID vaccines in particular. The allegation is that, since Facebook is following CDC guidance in deciding that the CHD's speech about vaccines is false and misleading, that means Facebook is effectively engaging in "state action" and so can be held liable under the First Amendment.
This would be controversial in general, and in particular since Rubenfeld is currently suspended from Yale due to sexual harassment issues. But at PrawfsBlawg, Howard Wasserman doesn't see how Rubenfeld's litigating on behalf of anti-vaxxers is different from the ACLU representing Nazis who want to march through Skokie. Both, in Wasserman's view, can be described as "the principled lawyer using civil litigation to pursue general ideals for all, albeit for the immediate benefit of the ultimate bad or unappealing person."
I have to admit, I don't share Wasserman's confusion. At least two things distinguish what Rubenfeld is doing from the ACLU's conduct in the Skokie litigation. The most obvious is that Rubenfeld has indicated that he thinks that the CHD's anti-vaccine conspiracies are true, not just constitutionally protected. The ACLU defended Nazis by saying that their speech, while abhorrent, is constitutionally protected. We'd look at them quite differently if there defense took Rubenfeld's form: "what the Nazis say about Jews is true (but even if it weren't, it'd be constitutionally protected)."
Second, the ACLU's position in Skokie was, as Wasserman states, a situation where the organization was defending a good constitutional that happened, in this case, to redound to the benefit of a bad actor. They were, in short, defending a bad client's bad position in service of a good principle. That doesn't translate if one thinks that the legal principle that would entail a victory for CHD over Facebook would be a bad principle (and not just bad because of its results in this case). In that case, Rubenfeld would be defending a bad client's bad position in service of a bad principle, which seems fairly characterized as bad.
The same applies to those who hopped on Trump's challenges to the 2020 Election. In addition to representing a bad client (Trump) and supporting him on the moral, not just legal, merits, and in addition to the case-specific outcome of his litigation being bad (overturning the democratic election results), the overall legal principles that would have been established (allowing states to reverse election results after the fact because they don't like the candidate who won the most votes based on specious claims of "fraud") would have been too. That's quite a bit of bad stacked on top of one another. And Rubenfeld, to me, seems to be in a similar circumstance, and can be judged similarly.