Richter is one of the Ward 6 patients in Mayfield Psychiatric Hospital who is extremly paranoid and thinks that the CIA are watching him. He appeared in the episode Broken. He was in Mayfield throughout the entire time that House was there. He was portrayed by Curtis Armstrong.
Richter is first introduced during Houses first group therapy session when he is concerned about Jay-Bird leaving the group. House diagnoses him with paranoia. Later on, when all of the Ward 6 patients are playing basketball, House tells Richter that the reason the CIA satellites aren't watching House but they are watching Richter is because Richter is wearing green. Richter immediately takes off his green sweater. After Dr. Nolan asks House if he has been getting to know the other Ward 6 patients, House tells him that Richter isn't as paranoid as he'd like them to think. During the Mayfield talent show, he, Jay-Bird and Hal sang "You're Nobody 'Til somebody loves you".
He currently still resides at Mayfield.