When an editor knows that a submitted article omits to reference key works in the area, what should he or she do?

What do members think of this?

An article in a major bioethics journal, on the role of empirical research in bioethics, fails to mention key references to prior work in the area, giving the illusion that the ideas are the author’s own.  A professor of bioethics in the UK writes a commentary in the same issue pointing out the ‘rather peculiar defect’ of the author’s paper: “It neither references nor discusses the already-extensive literature on the role of empirical research in bioethics. This defect cannot be because the literature is difficult to find. Running a simple search such as “empirical ethics” AND (“type of” OR “role of”) in a relevant search engine produces all the references to this commentary and many more.”.

This was the author’s response, again in the same issue of the journal:

“As most [journal name] readers know, there has been some excellent work done in this area previously, and I would doubt that not including such a discussion caused readers to believe that my work is the first attempt in this field. It would seem that one option would have been to provide a detailed description of all of the previous work in this area followed by fully developed arguments as to why I believe that these previous systems were insufficient. Such a discussion would likely take more space that the entire paper as written, therefore a complete and nuanced account would have engulfed the work. Alternatively, I could have provided [...] a brief overview of previous work without much detail and then briefly explained why I believe each is insufficient. I fail to see how such a thumbnail sketch would adequately inform the reader, and I would venture that my brief presentation of other scholars' work would have been met with criticisms that my simplistic renditions failed to adequately represent the sophisticated and nuanced schemes developed by these noted academicians. As such, it seemed appropriate to focus on what I wanted to say, say it as clearly and concisely as I could, and allow others to consider and comment. I am confident than many readers were already aware of this previous work, and those that were not and found this topic interesting likely decided to learn more about the topic and have already found the works cited along with others that impact this area. If not including the work of some scholars led to any sense that I failed to appreciate the importance of their work, that was certainly not my intention.

Is this a sufficiently robust explanation? Should the editors have insisted on proper referencing, especially after receiving the UK bioethicist’s commentary?  If this is unacceptable, is this a minor violation of publication ethics or is it more serious?  And what should be done now, if anything?