So you think that a colleague may have plagiarized or fabricated or libeled. What next?

You must marshal the facts. If you see an indication of plagiarism, print out the two texts and highlight the comparable passages for ease of comparison. If material appears to be fabricated or libelous, highlight the suspect text and itemize the reasons for concern. You must be as specific and thorough as possible, because you are holding another person’s career and reputation in your hands. It’s a good idea to consult with your immediate supervisor — for confirmation of the gravity of the case, and for backup.

You must go to the editor who supervises the writer. Do not confront the writer yourself. The assigning or supervising editor has direct responsibility for this writer and must be made aware of the situation.

Be careful how you phrase your remarks. I would never utter the words plagiarism, fabrication or libel or any equivalent. I would speak entirely about issues and concerns about the text. Talk in factual terms about the text without making accusations or personalizing the conversation. Your object is to permit the assigning editor to arrive at the same conclusion you did, or to provide persuasive reasoning otherwise.

But don’t be dissuaded easily. You are not just dealing with the reputation of the writer, but also with the reputation of the publication. If the outcome of this initial encounter does not satisfy you, you should not hesitate to go directly to the highest editor in authority who is available. This is one of the occasions on which you can and should call people at home.

Once you (or you and your supervisor) have done this, it is up to the higher authorities to talk to the writer, get an explanation of what happened and how, and adjudicate.

How they deal with such a potential scandal may influence your sense of whether you want to continue working for the publication.