Harvard Prof Says Trump Violates Constitution 'Constantly,' Calls For Impeachment Probe

President Trump's firing of FBI Director James Comey has led to renewed calls by Democrats for a special prosecutor to investigate Russia's influence on the presidential election and ties between the Trump campaign and Russia.

There are also calls for the president's impeachment. Harvard Law professor Laurence Tribe, a Constitutional law expert, makes the case for impeachment in newly-published opinion pieces in The Washington Post and USA Today. He joined Morning Edition to explain his reasoning.