Who was shown on the TV towards the end of the movie?

Near the end of Good Night, and Good Luck., when Ed and Fred are leaving William Paley's office after he cut down their show, they walk past a TV screen (on which the camera focusses before cutting to the frame story of Ed Murrow's speech) showing a speech of someone in a smoking talking about the habeas corpus principle and its implications (obviously in relation to the McCarthy case).

I wonder who was speaking in this apparently historical footage. I'm asking because I thought that might even have been footage of the real Edward R. Murrow, which would have been quite an anachronistic reference. But given the lack of acquaintance with the historical background of the story and the real persons involved I wasn't sure about this nor able to verify this guess that easily.