In the Iszoloscope tract "Heard Voices", where is the sample from?

There's a voiceover sample on the "endless noize" remix, it sounds like it's from a movie and the voice almost sounds like James Earl Jones. What I can make out is:

"I checked into the 20-year-old boy who killed his parents and his four brothers and his sisters, and when he was at trial he testified that he heard voices in the house. He heard voices in the house, and the voices told him to do it. Now I was in the house and I heard the voices, too, and I also felt the presence in the house. I tell you, there was a presence in that house!"

At first I thought it was from Exorcist II, but I don't think he played a character that would have been discussing trials in that movie. So maybe it was a different actor, or it was James Earl Jones in a different movie.

Anyone know?