Bill Cassidy, a Louisiana Republican, flip-flops his previous vote and sides with Democrats and 5 in GOP to proceed with Trump impeachment

• Sen. Bill Cassidy joined Democrats in voting to proceed with Donald Trump's impeachment.
• The Louisiana Republican told reporters he would be an "impartial juror."
• Cassidy was one of six Republicans to join 50 Democrats in moving forward with the case.

Sen. Bill Cassidy surprised Washington on Tuesday by joining with Democrats and a handful of other Republicans in voting to proceed with Donald Trump's impeachment.

Cassidy, a conservative from Louisiana, had last month sided with a majority of his caucus in seeking to block Trump's second impeachment trial in the Senate, supporting a motion from Sen. Rand Paul disputing the legality of trying someone who no longer holds elected office.

He flipped this week after being underwhelmed by the arguments presented by the former president's attorneys, joining five other Republicans and 50 Democrats in voting to move forward with the Senate trial. Trump stands accused of inciting the US Capitol riot on January 6 that left five people dead in the wake of the former president's false claims about an election he lost.

"I always said I'm gonna be an impartial juror," Cassidy told reporters after the vote.

"Anyone that listened to those arguments would recognize the House managers were focused," he said. "They relied upon precedent -- upon the opinion of legal scholars. Anyone who listened to President Trump's legal team saw they were unfocused. They attempted to avoid the issue. And they talked about everything but the issue at hand."

Democrats' lead impeachment manager, Rep. Jamie Raskin, opened Tuesday's proceedings with an emotional warning about the consequences if Trump is not held accountable for the actions of his supporters. "This cannot be the future of America," he said. "We cannot have presidents inciting and mobilizing mob violence against our government and our institutions because they refuse to accept the will of the people."

By contrast, Trump's lead attorney, Bruce Castor Jr., delivered a meandering speech that was mocked even by the former president's supporters. He "just rambled on and on," Texas Republican Sen. John Cornyn told reporters.

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