Some years ago, when I was modifying the ARCOM model paper layout to deal with issues of authorship, I suggested the following text: "Authorship should respect the rights of those involved in the production of the paper. The person who wrote most of the text should be the first-named author, even if this is a student. The sequence of authors should reflect the magnitude of each person’s contribution to the text of the particular paper. Supervisors, grant-holders and heads of department should not automatically be added as authors unless they took part in the writing of the paper. If a junior person wrote the paper, and a senior person helped with the editing, structuring and drafting, the senior person should be acknowledged in the acknowledgements, but merely helping to guide someone through the writing process does not warrant authorship."
A colleague on the ARCOM committee responded, thus: "I cannot come to terms with your recommendation to add a text in the Model Paper about the Authorship. I think it is too prescriptive and does not recognize the variety of possibilities that might well be legitimate. There are a diversity of efforts that go into undertaking a research and converting the results into papers. To reduce them into "the person who wrote the most of the text" is an understatement. Obviously there are certain practices that are not acceptable: not reading the paper on which your name comes first is on that radar and plagiarism is at the heart of that radar."
My response was: "I see what you mean. I agree that the world is more complex than the monochrome vision that I paint. And, yes, I agree that I am overstating the case. That is what I usually do! My reason for habitually overstating the case is that it makes it easier to explain, and easier to disagree with. Your rejoinder makes me realize that I should precede my suggested words by making it clear that they are only suggested guidelines which may result in a different approach for particular authors at particular times, but which would at least prompt an informed discussion between authors. My motivation is to empower junior authors to actually have this discussion with their senior co-authors. If they decide that this suggested policy is not appropriate in their case, then OK. I know it sounds prescriptive, but I did not mean to produce a set of rules, so, yes, I should re-phrase it. I wanted to provide an indication of what would be equitable, so that authors did not have to wait until they were more senior to become first authors, by which time they were no longer the primary progenitors of the text!"
Interestingly, none of this text is present in the guidelines now, so we must have got distracted by other matters. I still think that it is important to be clear about authorship of papers, and I still find that it is quite common for senior academics to have their names as authors despite sometimes having little or no involvement in the development or drafting of the paper.
The issue is important, and I quite like the Wikipedia entry about authorship