Somewhat telling that the Michigan congressman released his op-ed on the fourth of July,

Source: CNN

(CNN) Rep. Justin Amash, the only congressional Republican who publicly argues that President Donald Trump has engaged in impeachable conduct, announced Thursday he is quitting the GOP.

"Today, I am declaring my independence and leaving the Republican Party," Amash wrote in a Washington Post op-ed Thursday morning. "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."

Amash didn't mention the President by name, but his decision to abandon the party comes after months of escalating criticism not just of the President but of his own colleagues for their failure to hold Trump to account, specifically for the actions detailed in special counsel Robert Mueller's report on the 2016 election and its aftermath.