In this case, the journalists have confidential sources, they may forward that email to them, which would leak the source's IP, which could reveal the identity of the source.
A free and strong press is how we keep powerful institutions in check. It is not an inflammatory statement to say that a reprisal by a government institution that has been accused of doing something unethical is unethical. It's just common sense.
In case you decide to answer that question eventually, the model ethics rules are here: https://www.americanbar.org/groups/professional_responsibili...
I would really be interested in knowing which one you're alleging was violated.
IANAL, but clause (a) looks potentially applicable.
https://www.americanbar.org/groups/professional_responsibili...
> or use methods of obtaining evidence that violate the legal rights of such a person
I don't expect to see this prosecutor disbarred, but one can still call out the unethical behavior.
I am not aware of a legal right not to receive e-mail with remote-loading images.
Simply not liking someone's argument doesn't mean they didn't answer your question or are arguing in bad faith. To automatically assume that would imply that you are the one arguing in bad faith.