America's history of impeaching presidents

It's far from clear if the investigations being conducted by Robert Mueller in Washington will lead to any criminal charges, let alone an impeachment — but they are keeping the possibility alive.

For his "Truth, Politics and Power" series, former NPR host Neal Conan searched for historical insights on America's constitutional process for impeaching a president by examining our past two experiences: the impeachment trials of Andrew Johnson and Bill Clinton.

When the Constitutional Convention decided to put this constraint on the power of the president, they did not intend for it to be routine. Still, some believe Congress has been more timid to use the process than they ought to be.

"The idea that this power has become really something that is untouchable, that the standard is so grave that Congress is unwilling to use it ... when in fact the impeachment power is a sign I think of constitutional health," said Greg Weiner, an assistant professor of political science at Assumption College in Massachusetts, who spoke with Conan.

The idea is not to punish the individual, but to protect society, Weiner said.

Later in the program Conan spoke with Nina Totenberg, who has worked as a legal affairs correspondent at NPR for more than 40 years. In 1998 to 1999 Totenberg was part of the NPR team, which included Conan and the late Daniel Schorr, that provided live coverage of the impeachment proceedings against President William Jefferson Clinton.

Conan also spoke with David O. Stewart, an attorney who represented a federal judge at a Senate impeachment trial. He's also the author of several books, including "Impeached: The Trial of President Andrew Johnson and the Fight for Lincoln's Legacy."

Greg Weiner is author of several books, including "Madison's Metronome: The Constitution, Majority Rule, and the Tempo of American Politics."

To listen to the program, click the audio player above.