the first number corresponded to a tip from early in the hasse case, the tipster claimed to have overheard two men in a bar saying they'd killed mark hasse. that meant the tip came from william's computer. a follow-up computer search also revealed williams had searched several how-to websites. >> one of the websites was how to throw the police off an investigation by sending in fake tips. >> reporter: the second number on that scrap paper was even more important, because it turned out to be the real thing. it matched back to that computer message that gave details about the hasse murder weapon and also threatened more killings. >> so we knew right then that that tip that had come into the command post was sent by eric williams. and we knew right then we were gonna be able to put eric williams in jail. >> reporter: he was arrested, not for murder, but for making a terrorist threat about killing a judge.