In late 2018, Trump retweeted an image, later deleted, that showed former presidents Bill Clinton and Barack Obama behind bars, with the caption that suggested they should be tried for treason.
Trump was referring to the unfounded claims that his 2016 campaign was spied on by the Obama administration as part of a larger “deep state” initiative to undermine his presidential bid. It bears emphasizing that there is no evidence for what Trump was claiming, and even if it were true, it would not rise to the level of treason, which is a capital crime.
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In the lead-up to the 2020 election, Trump said that Biden should not be allowed to run for president, citing the same “treasonous plot.”
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On October 7, 2020, he tweeted, “Wow!!! NOW DO SOMETHING ABOUT THIS, THE BIGGEST OF ALL POLITICAL SCANDALS (IN HISTORY)!!! BIDEN, OBAMA AND CROOKED HILLARY LED THIS TREASONOUS PLOT!!! BIDEN SHOULDN’T BE ALLOWED TO RUN – GOT CAUGHT!!!”
Later that same day, Trump tweeted, “Obama, Biden, Crooked Hillary and many others got caught in a Treasonous Act of Spying and Government Overthrow, a Criminal Act. How is Biden now allowed to run for President?” The following day, Trump went on Fox Business and made his clearest statement to date, explicitly calling for both Obama and Biden to be indicted: ... Less than a week later, just twenty days before the election, Trump said at a rally in Des Moines, Iowa, “Now we can see clearly that Biden is a corrupt politician, who shouldn’t even be allowed to run for the Presidency.”