Washington post article is behind a paywall but I found another source
Research Firm Hired By Trump To Prove 2020 Election Fraud Came Up Empty: Report
A research firm investigated Donald Trump’s assertion that the presidential election was fraudulent, but its findings were suppressed because they found nothing to support his claims, The Washington Post reported citing four sources familiar with the matter.
The Berkeley Research Group, hired by the former president’s 2020 campaign, gathered a team of around a dozen people to look into alleged voter fraud and irregularities in six states, according to the Post.
The team reportedly briefed Trump, his former chief of staff Mark Meadows and others on a conference call held in the last days of 2020 — before Trump held a rally urging his supporters to march on the Capitol preceding the Jan. 6, 2021 insurrection. The call reportedly became contentious.
But the researchers had looked at “everything,” one source told the Post.
“Literally anything you could think of. Voter turnout anomalies, date of birth anomalies, whether dead people voted. If there was anything under the sun that could be thought of, they looked at it,” the source said.
Read more at this link
https://news.yahoo.com/research-firm-hired-trump-prove-233154305.html
