Dual publication of an article is generally not permitted. In signing the Agreement, you are being asked to represent that the contribution has not been submitted elsewhere for publication. There are narrow exceptions to the dual publication rule for some materials, such as standards. In any such case, prior approval from the journal to which you are submitting is likely to be required.
The Contributor's representations contained in the Agreement are designed to protect against plagiarism. Wiley policy is based on the 'Guidelines on Good Publication Practice' published by the Committee on Publication Ethics (COPE). COPE defines plagiarism as follows: "Plagiarism ranges from the unreferenced use of others' published and unpublished ideas, including research grant applications, to submission under 'new' authorship of a complete paper, sometimes in a different language... It applies to print and electronic versions."
It is the duty of journal editors to investigate suspected cases of misconduct. They need to decide whether it is necessary to retract a published contribution and in some cases, whether it is necessary to alert the employers of the accused author(s). Some evidence is required, but if the employers have a process for investigating accusations, it is not necessary for the editor to assemble a complete case as this may entail wider consultation which would bring the author into disrepute before the facts of the matter have been decided. Editors may decide not to involve employers in cases of less serious misconduct, such as dual publication, deception over authorship or failure to declare a conflict of interest. In all cases, authors must be given the opportunity to respond to accusations of misconduct before any action is taken.
The COPE guidelines have no legal force and it is generally prudent to avoid "naming and shaming" authors and simply to confirm a retraction, when necessary, in neutral and concise terms. The following sanctions are set out in the COPE guidelines, but journal editors should consider the application of any sanction very seriously due to the potential impact on an author's reputation or career:
Libel and slander are both forms of defamation and so in defining them, it is necessary to look at what is meant by "defamation." Broadly, defamation arises where a statement is made which is false and which impugns another person's reputation, or adversely affects his or her standing in the community.