Some four years ago I wrote about the strange case of a Canadian columnist accused of plagiarism. The Toronto-based Globe & Mail had found it necessary to add “clarifications” to articles written by Margaret Wente after complaints about her work.

Wente defended herself at the time by writing: “I’m far from perfect. I make mistakes. But I’m not a serial plagiarist.” But she went on working for the paper.

Now a new storm has blown up that calls her 2012 defence into question. On Saturday, Ottawa university professor Carol Wainio, whose research led to the original controversy, raised concerns on her blog about Wente’s 23 April column.

She pointed to the fact that Wente has used an “identical sentence” to one that had appeared previously in an article by Jesse Ausubel. Wainio also mentioned other similarities involving an article by researcher Maywa Montenegro.

The allegations were taken seriously enough by the Globe & Mail for it to append a note to Wente’s column that apologised to Ausubel, adding: “This online version has been corrected with the proper attribution. In addition, the link to the original academic research by food systems researcher Maywa Montenegro has been included.”

Soon after, a BuzzFeed Canada article quoted a New York University professor, Charles Seife, who had noted that a phrase in a Slate article by Daniel Engber had appeared a week later in a 12 March column by Wente without direct attribution.

The following day, another BuzzFeed article alleged that there were “striking similarities” between a book review in the New York Times magazine and a column by Wente which was published 10 days later, on 27 February 2016.

According to Buzzfeed’s analysis, “much of Wente’s Globe & Mail column about the same book reads like a mirror of the Times’s piece, using the same structure, analogies, and phrasing in numerous instances.”

In addition, the Canadaland news website, accused Wente of plagiarising “at least four times from three different publications... in addition to the two cases of plagiarism outlined in BuzzFeed Canada.”

The first two instances, by Wainio and BuzzFeed, were addressed by the Globe & Mail’s public editor, Sylvia Stead, in a lengthy posting on Monday.

She pointed out that the paper’s code of conduct said it was” unacceptable to represent another person’s work as your own” and that “excerpts from other people’s prose must be attributed so as to avoid even a suspicion of copying.”

Stead wrote that there would be corrections and apologies for what she called Wente’s “mistakes.”

And she included a statement by the paper’s editor-in-chief, David Walmsley, saying: “This work fell short of our standards, something that we apologise for. It shouldn’t have happened and the opinion team will be working with Peggy to ensure this cannot happen again.”

Working with Peggy to ensure it doesn’t happen again? How does that work, I wonder? And what of the other allegations by BuzzFeed and Canadaland? More work with Peggy may be required.