Law & Order: Special Victims Unit Guest cast, played by Peter Riegert Episode 5x19: Sick (Mar 30, 2004) Episode 5x20: Lowdown (Apr 6, 2004) Episode 6x06: Conscience (Nov 9, 2004) Episode 7x22: Influence (May 16, 2006) Episode 8x13: Loophole (Feb 6, 2007) Episode 9x04: Savant (Oct 16, 2007)