I just sent this email to a scientific editors' email forum. If you are interested in commenting, please add your comments to this blog, and I can include them in a summary of the discussion:
I am interested in the phenomenon of authors adding co-authors to their papers, without first consulting the so-called co-authors. I get the feeling that this is something that is rare, but gradually increasing. I think that people might do it to make their papers look more authoritative, or to drive up citations by adding a highly-cited author. Clearly, it is bad practice and I was wondering what could be done to ensure that it does not happen.
My impression from the publishers is that their aim is to ensure that if it does happen, they are not culpable. They will have had the corresponding author sign a declaration that all of the authors are aware of the paper and are validly listed as co-authors. Yet this does not overcome the problem, it merely moves the liability for the problem, in my own view.
Is this something we should be worried about? Should we seek explicit acknowledgement from each author that they have indeed played an instrumental role in the production of the paper? Or is it sufficient to identify this as the sole responsibility of the corresponding author? I would very much like to hear your thoughts on this issue.