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Last week, President Trump stirred up controversy when he criticized former U.S. Ambassador to Ukraine Marie Yovanovitch over Twitter while she was testifying in the impeachment inquiry. Trump's opponents argued it could be construed as witness intimidation, but the White House apparently didn't think so.

During Lt. Col. Alexander Vindman's impeachment testimony Tuesday, the White House followed Trump's playbook and tweeted a graphic highlighting a quote that questioned Vindman's credibility as a witness.

Vindman's old boss, former National Security Council official Tim Morrison (who will testify publicly Tuesday afternoon), reportedly once said he was concerned about Vindman's judgment, which was brought up during Tuesday's public hearing by Rep. Jim Jordan (R-Ohio). Vindman addressed Morrison's comments and said that while he couldn't be sure exactly what caused Morrison to feel that way, he believes it likely had to do with the fact that the two hadn't worked together long at that point and were still developing their working relationship.

As CNN's Jake Tapper points out, the White House technically went after its own employee in this instance. Tim O'Donnell