"I know it when I see it," said forensic psychiatrist Michael Welner, chairman of the Forensic Panel, psychiatrists who consult in legal cases.

So Welner, a New York psychiatrist who led a forum at this week's meeting of the American Psychiatric Association, has decided to "wade in the cesspool of this topic" and try to figure out if people of different ages, sexes, religions and races can agree on what constitutes depravity. He's developing a "depravity scale" based on an online survey about criminals' intent, actions and attitudes. Participants decide whether an act is especially, somewhat, or not depraved.