Question: When authors submit paper to a journal, the paper will go through the peer review process. When a reviewer accepts to review a paper, the reviewer is then given the power to delay the publication of the paper and the power to reject the paper. From time to time, it has been shown that reviewers abuse the power to commit misconduct. There are many types of misconduct that a reviewer can do, one example is slowing down the review process so that other papers with the same topic have the chance to get published first.

Another example (and considered as the worst misconduct that reviewer can do) is a reviewer plagiarizing the paper that they reviewed and submitting the plagiarized paper to other journal. In 2016, a reviewer from a high-level journal plagiarized and submitted a paper to another journal (read: [[1]](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6310661/) [[2]](https://retractionwatch.com/2016/12/12/dear-peer-reviewer-stole-paper-authors-worst-nightmare/)), which showed that even high-level journals are not immune from this misconduct.

Due to the sheer volume of papers that a journal must process, it is hard for an editor to determine whether the rejected paper is actually a "bad" paper, it is possible that a reviewer intentionally rejected the paper for malicious intent. The same goes for a situation when a reviewer intentionally makes the review process as slow as possible, it is hard to detect whether they intentionally slow down the publication of the paper.

Is there anything we can do to protect ourselves from predatory reviewers?

Answer: 
I think the question is based on an irrational fear. Let me explain why, assuming that we are talking about high-quality journals rather than ones run by predatory outfits.

First, reviewers do not actually have the power to do anything. They only *recommend* what the editor should to do, but the power to reject a paper rests with the editor. And editors almost always know the field well and can judge whether a paper should be rejected; in fact, I suspect that in the majority of cases, editors will know whether a paper should be rejected based on their own reading of the manuscript, but expert reviewers are necessary to provide a more complete picture. As a consequence, if one reviewer suggests rejecting a paper, but others suggest accepting or revising it, editors will use their professional judgment to adjudicate the conflicting opinions and will be able to tell who is right and who is not. In practice, this decision-making is helped by the fact that editors often know the reviewers at least casually.

Second, while it is of course true that humans -- including reviewers -- have generally done nearly every ethically unbecoming thing one could imagine, this does not mean that it is common. I've been an editor of journals for more than a decade, and editor-in-chief for four years, but I cannot recall seeing or hearing about reviews that were ethically questionable despite reading hundreds of them. I've seen many reviews that were lazy, but I can't say that I saw any where I thought that a reviewer suggested an outcome that was not backed by at least some kind of objective reasoning.

As a consequence, my suggestion would be to focus on (i) writing good papers, (ii) sending them to good journals, (iii) posting the manuscript on some kind of preprint server.
Predatory reviewers are so rare there is no need to do anything to protect yourself. It's so easy to get caught plagiarizing a paper you are reviewing that anyone who does it will have quite a short career. The probability that your reviewer has a similar paper near publication is very low.

If a reviewer is malicious, intentionally making the author's life difficult, then it is the editor's responsibility to discard the review. Similarly, if the reviewer requests inappropriate citations, it is the editor's responsibility to decline.