Research integrity guidelines have quite a bit to say about what is expected of authors in terms of contributions and research performance, but much less about the responsibilities of co-authors in cases of scientific misconduct.

According to the Council of Science Editors (CSE), an international organization for science editors, “The ultimate reason for identification of authors and other contributors is to establish accountability for the reported work”. CSE specifies: “Authors are individuals identified by the research group to have made substantial contributions to the reported work and agree to be accountable for these contributions.” Each author is “accountable for the parts of the work he or she has done”. In the CSE White paper on promoting integrity in scientific journal publications (CSE 2012), wherefrom the quotes are taken, there are no suggestions that each author, or some author, is responsible for what other contributors do, although authors are expected to be aware of the collaborators’ contributions.

The Recommendations for the conduct, reporting, editing, and publication of scholarly work in medical journals, issued by the International Committee of Medical Journal Editors (henceforth the ICMJE guidelines), and the most influential authorship guidelines to this day, have through their different versions strongly stressed the idea that all authors of a paper should share not only scientific credit for the work but also responsibility for that paper (ICMJE 2016). This also explains why it has been insisted that all authors not only do some substantial contribution to the research, but also participate in the writing or critical revising of the paper, in order to qualify as authors—unless you read the paper critically, you cannot take responsibility for it (cf. Strange (2008, C567): “You can only assume responsibility if you were intellectually engaged in the work and in writing the manuscript”). But the exact message has varied between versions, from the view that each author is responsible for the entire paper to the view that each author is responsible at least for their own contribution. In the latest version, it is stated:

In addition to being accountable for the parts of the work that he or she has done, an author should be able to identify which co-authors are responsible for specific other parts of the work. In addition, authors should have confidence in the integrity of the contributions of their co-authors.

The fourth criterion for authorship further requires:

Agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

This implies that authors should not only know and take responsibility for their own contributions to the paper, but they should know enough about the collaboration as a whole to be able to say, for instance, who else were included in the collaboration and what they contributed—which implies being able to help identify who did what if, for instance, certain analyses turn out to be fraudulent.

It has been suggested to us on several occasions in conversation that the fourth criterion should be taken to imply that all authors have personal responsibility for all parts of the work, a view echoed in the literature (e.g. Kornhaber et al. 2015; Leventhal 2016). But this seems to be a reasonable interpretation only if one stops reading after the first occurrence of “the work”. The fourth criterion rather seems to say that each co-author must collaborate with misconduct investigators (for instance, by providing research protocols or relevant email conversations upon request) if their paper is called into question.

In a position statement developed at the 2nd World Conference on Research Integrity 2010,Footnote 1 supported by the Committee on Publication Ethics (COPE) and published at the COPE website (Wager and Kleinert 2011), it is stated that research should be carried out in an ethical manner, should be sound and carefully executed, using appropriate methods, and should be presented in an honest, correct, and non-misleading way—but also that authors “should take collective responsibility for their work and for the content of their publications” (Section 1.4). Later in the position statement (Section 7.1) this proposal is specified as follows:

In most cases, authors will be expected to take joint responsibility for the integrity of the research and its reporting. However, if authors take responsibility only for certain aspects of the research and its reporting, this should be specified in the publication.

ALLEA (“All European Academies”, i.e., The European Federation of Academies of Sciences and Humanities), in its 2017 edition of The European Code of Conduct and Research Integrity, concurs with this understanding of authorship responsibility: “All authors are fully responsible for the content of a publication, unless otherwise specified.” The shared idea here seems to be that the primary option should be that all authors share the responsibility equally for the paper in case of scientific misconduct. The only circumstances under which not everyone should be held equally responsible are when limitations in this regard are specifically stated in the publication.

On the account that such specifications are rarely made (journals requiring a contribution statement are in a clear minority), there is disagreement between on the one hand the CSE and the ICMJE guidelines and on the other the COPE-supported position statement/ALLEA regarding the responsibility of the individual author. Where COPE/ALLEA requires everyone to assume equal responsibility for misconduct also when only a limited few are actually guilty, the CSE/ICMJE guidelines suggest that those who did it should assume responsibility for it. COPE/ALLEA can perhaps be read as promoting a practice where limitations in responsibility are standardly described in the paper by concerned authors, rather than favouring blaming all authors if the paper is fraudulent. This would be in line with the declaration, for instance, of the journal PLOS One (at http://journals.plos.org/plosone/s/authorship): “We expect that all authors will take public responsibility for the content of the manuscript submitted to PLOS. The contributions of all authors must be described.” But if this is what COPE/ALLEA mean, then they should say so.

Importantly, it is not clarified in any of these sources whether or not declarations of contributorship, as presently used by some journals, would be sufficient ground for differentiation in accountability. Rennie et al. (1997) argued that this would be the very point of contributorship statements and that they should be made compulsory. Let us conclude that a more widespread application of the practice of making contributorship declarations would support a practice of distinguishing between the different responsibilities of different authors.