WASHINGTON — Monica Crowley, the Treasury Department’s assistant secretary for public affairs, committed “localized instances of plagiarism” in her 2000 Ph.D. dissertation, Columbia University found in an investigation that ultimately concluded she did not commit research misconduct.
As part of the university’s review of Ms. Crowley’s work, she was required to make extensive revisions to her dissertation, a 493-page study of how American policy toward China evolved under Presidents Harry S. Truman and Richard M. Nixon. The research misconduct investigation, which concluded this month, was started after plagiarism accusations were raised about her work in 2017 after her appointment by Donald J. Trump, then the president-elect, for a senior National Security Council job.
“The investigation identified localized instances of plagiarism, but concluded that the preponderance of the evidence did not support a finding that Dr. Crowley committed research misconduct,” the university said.
Ms. Crowley, a former Fox News contributor and prominent conservative pundit, has served as Treasury Secretary Steven Mnuchin’s top spokeswoman since July.
“I am delighted that they have concluded that there was no research misconduct, as I have maintained all along,” Ms. Crowley said. “I was also happy to address any inadvertent and honest errors and update the work.” She added, “I am extremely proud of the dissertation, particularly given the fresh timeliness of its subject — the U.S.-China relationship — and hope that others will read and appreciate it.”
Columbia University’s statement about its findings was appended to the top of a 27-page “errata sheet” that was added this month as a supplemental file to Ms. Crowley’s dissertation. The supplemental file includes 32 revised passages that contained plagiarism or other citation deficiencies that required correction. Two books and two articles were added to the bibliography.
Questions about Ms. Crowley’s writing surfaced in 2017 when Politico Magazine published an investigation that found about a dozen examples of plagiarism, including paragraphs that were essentially copied from other scholarly works, heavy paraphrasing and a failure to properly cite or attribute other research.
A Columbia spokesman said the university created a small faculty committee in 2017 to decide whether the accusations were serious enough to warrant a full investigation. After it was determined that was needed, a separate committee considered the accusations and presented its findings and a recommendation to Columbia’s Standing Committee on the Conduct of Research. That committee then made a recommendation to the provost.
In cases of academic fraud, Columbia could revoke a degree entirely or ask a student to revise his or her work. In the case of Ms. Crowley, who received her doctorate in international relations, the university required the revisions to be appended to the dissertation as a way of demonstrating the seriousness of the problems.
The questions in 2017 about Ms. Crowley’s dissertation coincided with a CNN report that found about 50 examples of plagiarism in Ms. Crowley’s 2012 book, “What The (Bleep) Just Happened,” which was a critique of the Obama presidency. At the time, HarperCollins, which published the book through its conservative imprint Broadside Books, withdrew the digital edition from retailers. Last year, the publisher returned an updated version it to the market after Ms. Crowley “addressed a number of inadvertent textual errors.”
After the controversy, Ms. Crowley withdrew from the National Security Council role, which would have involved speechwriting. She did not address the plagiarism accusations at the time, but in a 2017 appearance on Fox News, she told Sean Hannity that they were a “despicable, straight-up political hit job.” She also said that the claims had been “debunked.”
Ms. Crowley, an early supporter of Mr. Trump, joined the Treasury Department in the spring as a senior adviser in public affairs after Mr. Mnuchin’s spokesman at the time, Tony Sayegh, announced in April that he would leave over the summer. She was brought on as part of a broader effort to bolster the Trump administration’s messaging on the economy going into the 2020 presidential campaign.
The position did not require Senate confirmation. However, Senator Ron Wyden of Oregon, the top Democrat on the Finance Committee, released a statement when Ms. Crowley’s appointment to be the Treasury Department’s top communications official was announced in July. He argued that evidence of plagiarism should have been disqualifying for a senior government official.
Mr. Wyden’s office also sent a letter to Columbia University to inquire about the status of Ms. Crowley’s degree.
“Plagiarism is a serious offense that may result in expulsion from college, but is not even a red flag for the Trump administration,” Mr. Wyden said. “Credibility should be nonnegotiable in Ms. Crowley’s position.”
Plagiarism at times has been a disqualifying offense in politics. In 2014, John E. Walsh, then a Democratic senator from Montana, withdrew from an election after The New York Times reported that he plagiarized large sections of a paper he needed to graduate from the Army War College, which later revoked his master’s degree.
In 1987, then-Senator Joseph R. Biden Jr. withdrew from a race for the Democratic presidential nomination after it came to light that he had lifted portions of other people’s speeches without attribution and plagiarized part of a law review article for a paper in law school.
More recently, episodes of plagiarism have been overlooked. In 2016, speechwriters for Melania Trump, Mr. Trump’s wife, were caught having used passages that appeared to come from speech by Michelle Obama, the first lady at the time, after Mrs. Trump delivered an address at the Republican National Convention. Despite a brief uproar, the controversy quickly blew over.
And Stephanie Grisham, the White House press secretary, once lost a job at an advertising agency after she was accused of plagiarizing information for a presentation, The Times reported in August.
Ms. Crowley has generally been seen as a positive presence at the Treasury Department. Since assuming the job, she has expanded the department’s communications team, updated its presence on social media and encouraged Mr. Mnuchin to participate in more interviews and briefings at a variety of forums.