Trump's Defiance on Impeachment Tests the Constitution

President Donald Trump and Democrats in the U.S. House of Representatives are in a constitutional standoff over impeachment. The White House is refusing to furnish witnesses and documents demanded by Democrats for their inquiry into his phone conversation with the president of Ukraine. The clash is raising fundamental questions about the power of the presidency, the balance of powers under the U.S. Constitution and the state of American democracy. VOA National correspondent Jim Malone has more