Let's consider the following situation:
Author A submits a paper to a journal. Referee B writes a critical referee report and recommends rejection. Author A then resubmits the same paper to another journal managed by Editor C with no edits made. As luck has it, Editor C asks Referee B to referee the paper again.
Let's assume here that Referee B's criticisms are valid. My questions are:
At what point do Author A's actions become unethical? Can they count as research misconduct?
Assuming Author A's actions are misconduct, what actions should be taken by Referee B? By Editor C once the issue is exposed?
My understanding is that it would be unfortunate to attempt to republish someone else’s work without being aware of it, but would be considered misconduct to do so intentionally. So I guess Questiin 1 is partially asking if Referee B’s report should be construed as prior knowledge.
I'm also aware that the critiques Referee B give influence the outcome of Question 1. Some, like omitting critical details of a proof in a math paper, are field specific. Others are more universal, like refusing to cite prior work that contains some of the claimed results.
Edit: question 1 has been edited to use less strong language.