I tend to think my credentials as a fan of the First Amendment are pretty solid. But I feel like I’m standing on pretty solid ground in saying that a lawyer’s effort to pursue a ballot initiative that calls for the murder of people, if it were going on in Tennessee, would justify discipline against their license under RPC 8.4(d) as “engag[ing] in conduct prejudicial to the administration of justice.” All of the rest of the stuff pursued in the initiative would seem to be well-entitled to First Amendment protection – whether simply on the basis of the exercise of rights of political speech or petitioning the government for redress of grievances, or both. Calling for executions — particularly through a provision that would “deputize” members of the public to do so — seems like the kind of thing lawyers ought to be able to agree is several bridges too far.
That said, I was surprised to see quotes from more than one California counsel taking the view that no discipline in California would likely be available. I’m guessing though that has more to do with California still not having rules patterned after the ABA Model Rules and, thus, not having a rule such as RPC 8.4(d) on the books.