Botanist Steven Newmaster, whose controversial work profoundly influenced how dietary supplements are tested and marketed, did not engage in scientific misconduct, a University of Guelph (UG) investigation committee has ruled.

Newmaster “displayed a pattern of poor judgement and failed to apply the standards reasonably expected in research activity in his discipline,” panel chairman John Walsh wrote today in a letter to the eight scientists who lodged a complaint against Newmaster last year. Yet despite “many shortcomings” in his work, the panel said there was “insufficient evidence” to find Newmaster guilty of misconduct in three studies that his accusers had singled out.

“Given the evidence of data falsification that was assembled, I was very surprised at the conclusion,” says evolutionary biologist Paul Hebert, a signatory to the complaint who directs UG’s Centre for Biodiversity Genomics. Newmaster did not respond to a request for comment today.

Newmaster specializes in applying DNA barcoding, a technique pioneered by Hebert that identifies biological species based on snippets of DNA, to plants and plant products. In a 2013 BMC Medicine study, he accused the industry of selling substandard products tainted with toxic contaminants. The paper drew international media coverage and led to a crackdown on the products by New York’s attorney general.

The study also propelled Newmaster to global fame as a testing expert and industry advocate. His private companies and a nonprofit group at UG raised millions of dollars by certifying supplements, cannabis, and other comestibles.

A 43-page complaint filed with the university in June 2021 by Hebert and other scientists—including co-authors on two of Newmaster’s papers—said Newmaster committed data fraud and plagiarism and didn’t disclose conflicts of interest as required. Their complaint focused on the 2013 supplements study, which BMC Medicine has since placed under investigation; a 2014 article about the use of DNA barcoding to identify forest plants that was retracted in 2021; and a 2013 paper in the Canadian Journal of Forest Research—to which the journal has added an Expression of Concern—that explored the use of DNA barcoding to determine woodland caribou diets.

Newmaster denied all charges in the complaint last year. “I have never engaged in any unethical activity or academic misconduct,” he wrote in an official reply obtained by Science.

An investigation by Science published in February, based on a review of thousands of pages of Newmaster’s work as well as his videos, PowerPoint presentations, and websites, revealed numerous other cases in which he appeared to manipulate or fabricate data, plagiarize, and invent elements of his academic record. Newmaster declined to comment for the Science story, and the panel did not address those additional issues.

Today’s letter to the complainants summarizes the panel’s conclusions but provides few details about its reasoning. UG has yet to issue its final decision, a process that could take several months. A spokesperson did not respond to a request for comment about whether Newmaster could be sanctioned for the problems in his work that the committee identified. UG policy suggests he would not be subject to penalties of any kind.

“This was an entirely credible and well-founded allegation with a lot of evidence,” says

Stanford University postdoctoral fellow Ken Thompson, a complaint signatory who was the first to cast doubt on Newmaster’s work in 2020. UG dismissed Thompson’s concerns on several occasions and did not launch a formal investigation until the group of eight scientists filed its complaint.

As a UG undergraduate working with Newmaster, Thompson was a co-author on the study of forest plants. Years later, Thompson realized Newmaster had never shown him the raw data or uploaded them to a data repository, as required. Newmaster and a colleague appeared to use records from an unrelated experiment in an unsuccessful effort to validate the work, according to the misconduct complaint. The journal Biodiversity and Conservation retracted the paper in October 2021, citing several serious problems. “The Editor-in-Chief … no longer has confidence in the validity of the data reported in this article,” the retraction notice said.

Newmaster’s accusers had expressed concerns that the investigation might not be rigorous, given the panel members’ lack of expertise in genomics. Walsh is acting associate dean of UG’s Gordon S. Lang School of Business and Economics, Jeff Wichtel is the dean of UG’s veterinary college, and Cynthia Fekken is a psychologist from Queen’s University. They were aided by an expert witness who has not been identified. Walsh did not respond to a request for comment today.

Thompson is particularly frustrated that the committee says the misconduct allegations are not supported because of “the absence of records and data. … That was the essence of our complaint,” he says. “We knew they wouldn’t be able to find records. Our complaint alleged that Prof. Newmaster falsified his work and never had the data to back it up. That’s really disappointing.”

“There’s a big question that we need to ask ourselves as scientists working in Canada,” Thompson adds. “Do we actually care about addressing misconduct?”

This story was supported by the Science Fund for Investigative Reporting.

Update, 2 June, 1:15 p.m.: A reference to the Expression of Concern about Newmaster’s 2013 paper in the Canadian Journal of Forest Research has been added to this story.