Story highlights "It's very frustrating as I'm sure you can imagine," he said

Schaffner labeled the administration's claims as "absurd" and "not even plausible"

(CNN) One of the academics who produced data suspected of being behind the White House's assertion that millions of illegal votes were cast in 2016 says the Trump administration and other academics are misinterpreting his research.

Brian Schaffner, a political scientist at the University of Massachusetts, told CNN's Wolf Blitzer on "The Situation Room" Tuesday his study on voter fraud that is apparently being cited by the White House did not support the President's conclusions.

White House press secretary Sean Spicer did not say expressly on Tuesday which study Trump has read to support his claim of 3 to 5 million illegally cast votes, but a 2014 study by Jesse Richman and David Earnest found more than 14% of non-citizens in 2008 and 2010 "indicated that they were registered to vote."

The study was designed by Schaffner's Cooperative Congressional Election Study, but he told Blitzer that he and his colleagues spoke with voters who had self-identified themselves as "non-citizens" and discovered that they had all mistakenly clicked the wrong radio button during the survey -- and they were all actually citizens.

"It's very frustrating as I'm sure you can imagine. The data certainly do not show that," he said of the White House's claims. "Of the people who we were sure were non-citizens, we could not find any who actually cast a vote."

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