Michael Ian Campbell, 18, answered 30 minutes of questions from U.S. District Judge Edward Nottingham before the judge accepted his guilty plea to one felony count of communicating a threat across state lines.
Campbell could get five years in prison and a $250,000 fine when he is sentenced April 28. Prosecutors agreed to recommend a lenient sentence, but Nottingham is not obliged to accept the recommendation.
Campbell, of Cape Coral, Fla., is accused of telling a Columbine student in a Dec. 15 e-mail that he would "finish what begun" at the high school last April, when Dylan Klebold and Eric Harris killed 12 students, a teacher and themselves.
Authorities who learned of Campbell's threat shut down Columbine two days before Christmas vacation as a precaution. Campbell was tracked to his Florida home via his Internet provider, America Online.
Campbell originally pleaded innocent. His lawyer, Ellis Rubin, outlined an ``Internet intoxication defense,'' claiming Campbell couldn't distinguish between reality and cyber-reality because of prolonged exposure to the Internet.
