Twenty years ago, Justice Clarence Thomas was confirmed to the Supreme Court by the narrowest margin in 100 years. He's the most conservative justice since the 1930s, and, in his passion for his own version of "original intent," he's willing to reverse whole lines of previous rulings. He's an enigmatic figure — silent at oral arguments, beloved by his law clerks and court employees. Most analysts say that his extreme views limit his influence on the court, except to set markers for where a future court could go. NPR's Nina Totenberg reports.