A former technical adviser to the January 6 committee discussed the investigation with "60 Minutes."
Denver Riggleman said texts from Mark Meadows showed a "roadmap" to overturning the election.
Meadows was receiving texts about the alternate electors plot just days after the election.
A former technical adviser to the January 6 committee said texts former White House Chief of Staff Mark Meadows turned over provide "irrefutable" proof of a plot to overturn the results of the 2020 election.
Denver Riggleman, a former Republican congressman, made the comment during an interview with CBS News' "60 Minutes" on Sunday. He said Meadows' texts showed a "roadmap" for how allies of former President Donald Trump were trying to overturn the election.
"It showed actually the evolution of the beginning arguments from alternate electors all the way through rally planning, all the way to day of," he said.
Host Bill Whitaker asked Riggleman to confirm his belief that Meadows' texts "provide irrefutable, time-stamped proof of a comprehensive plot at all levels of government to overturn the election."
Riggleman responded affirmatively: "Irrefutable. Early in the text messages they were talking about alternate electors, you know, I think as soon as November 5th or November 6th."
Whitaker went on to note the many text messages Meadows had received in the days after the election, including one from Donald Trump Jr. in which he explained an alternate electors plan that would allow his father to win pending Congress's actions on January 6.
Meadows, who was Trump's chief of staff from 2020 to 2021, was also receiving texts about how to address the "stolen" election from people like MyPillow CEO Mike Lindell and GOP Rep. Marjorie Taylor Greene. Insider previously compiled a list of all the texts Meadows had received while the January 6 insurrection was unfolding.
"The Meadows text messages show you an administration that was completely eaten up with a digital virus called QAnon and conspiracy theories: an apocalyptic, messianic buffoonery. You can look at the text messages as that roadmap, but it's also a look into the psyche of the Republican party today," Riggleman said.
Riggleman noted it's unclear if Meadows turned over all of his relevant texts but said "what we got is pretty valuable."
A lawyer for Meadows did not immediately respond to Insider's request for comment.