GRAND RAPIDS, Mich. (CBS DETROIT/ AP) — The only Republican in Congress to call for impeachment proceedings against President Donald Trump, said said Thursday he is leaving the GOP.

Rep. Justin Amash of Michigan, said he has become disenchanted with partisan politics and “frightened by what I see from it.”

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He wrote an opinion article published in the Washington Post July 4 and said partisan politics is damaging American democracy.

“I am declaring my independence and leaving the Republican Party,” Amash said. “I’m asking you to join me in rejecting the partisan loyalties and rhetoric that divide and dehumanize us.”

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In a series of tweets May 18, Amash said that he had read special counsel Robert Mueller’s report on Russian meddling in the 2016 presidential election, and concluded that Trump “has engaged in impeachable conduct.”

Since his call for impeachment against Trump, he was roundly criticized by fellow Republicans and withdrew from the Freedom Caucus of conservatives in Congress after the group disavowed his views.

Amash had filed in February for re-election in 2020 as a Republican in a race that has since drawn three primary challengers, his first intra-party challenge since 2014. Amash’s chief of staff, Poppy Nelson, said Thursday that Amash plans to run as an independent.

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