Army officer who heard Trump's Ukraine call voiced his concerns to superiors

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Lt. Col. Alexander Vindman plans to tell House impeachment investigators that he heard Trump appeal to Ukraine's president to investigate one of his leading political rivals, a request the aide considered so damaging to American interests that he reported it to a superior. Lawrence O’Donnell discusses with Josh Lederman, Michael McFaul, Evelyn Farkas, and Jonathan Alter.