Trump impeachment primer: What to expect from the 3rd ever impeachment of a president, from someone who reported on the Clinton impeachment

KNXAM: On-Demand
Thursday, January 16th
For only the third time in American history, the U.S. Senate has opened an impeachment trial  of a U.S. President. Senators serve as jurors, and the Chief Justice of the Supreme Court presides. Opening arguments are set for next week.

But even as this historic trial gets underway, there are new and troubling developments:

-A long time associate of Rudy Giuliani  claims that there was a well established plot to pressure Ukraine to announce an investigation of former Vice President Joe Biden and his son.

-And a ruling by a U.S. government watchdog agency says the Trump administration's withholding of congressionally approved aid to Ukraine was illegal.