Rep. Justin Amash, who represents Michigan’s 3rd Congressional District in the U.S. House, wrote in a Washington Post op-ed Thursday morning that he is leaving the Republican Party.

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In the piece, Amash rails against what he calls "partisan loyalties and rhetoric that divide and dehumanize us."

Here's an excerpt:

My parents, both immigrants, were Republicans. I supported Republican candidates throughout my early adult life and then successfully ran for office as a Republican. The Republican Party, I believed, stood for limited government, economic freedom and individual liberty — principles that had made the American Dream possible for my family.

In recent years, though, I’ve become disenchanted with party politics and frightened by what I see from it. The two-party system has evolved into an existential threat to American principles and institutions.

Today, I am declaring my independence and leaving the Republican Party. No matter your circumstance, I’m asking you to join me in rejecting the partisan loyalties and rhetoric that divide and dehumanize us. I’m asking you to believe that we can do better than this two-party system — and to work toward it. If we continue to take America for granted, we will lose it.

Read more here.

Earlier this year, Amash's comments recommending Congress pursue obstruction of justice charges against President Trump were the first instance of a sitting Republican in Congress saying the President's conduct meets the "threshold for impeachment."

"Our system of checks and balances relies on each branch's jealously guarding its powers and upholding its duties under our Constitution," Amash tweeted. "When loyalty to a political party or to an individual trumps loyalty to the Constitution, the Rule of Law -- the foundation of liberty -- crumbles."

Amash's district is based in Grand Rapids, including most of its suburbs and the city of Battle Creek. Now he's no longer a Republican and considered an Independent. He sent this tweet at midnight: