It’s been an eventful month, with the House of Representatives’ impeachment inquiry into President Trump becoming a font of high-profile depositions, bombshells, attacks and counter attacks. Further action on impeachment may well hang on four words in the U.S. Constitution: high crimes and misdemeanors. Dr. Buckner F. Melton Jr. is a professor of history and political science at Middle Georgia State and author of The First Impeachment . He joined On Second Thought to help explain what “high crimes and misdemeanors” means, and how the phrase ended up in the Constitution in the first place.