HOUSTON - "Affluenza," the affliction cited by a psychologist to argue that a teenager from a wealthy family should not be sent to prison for killing four pedestrians while driving drunk, is not a recognized diagnosis and should not be used to justify bad behavior, experts said Thursday.

A judge's decision to give 16-year-old Ethan Couch 10 years of probation sparked outrage from relatives of those killed and has led to questions about the defense strategy. A psychologist testified in Couch's trial in a Fort Worth juvenile court that as a result of "affluenza," the boy should not receive the maximum 20-year sentence prosecutors were seeking.

The term affluenza was popularized in the late 1990s by Jessie O'Neill, the granddaughter of a past president of General Motors, when she wrote the book The Golden Ghetto: The Psychology of Affluence. It has since been used to describe a condition in which children - generally from richer families - have a sense of entitlement, are irresponsible, make excuses for poor behavior, and sometimes dabble in drugs and alcohol, said Gary Buffone, a Jacksonville, Fla., psychologist who does family wealth advising.

But he said in a telephone interview Thursday that the term wasn't meant to be used as a defense in a criminal trial.

Authorities said the teen and friends were seen on surveillance video stealing two cases of beer from a store. He had seven passengers in his Ford F-350, was speeding, and had a blood-alcohol level three times the legal limit, according to trial testimony. His truck slammed into the pedestrians, killing Brian Jennings, 43; Breanna Mitchell, 24; Shelby Boyles, 21; and her mother, Hollie Boyles, 52.

Judge Jean Boyd decided the programs available in the juvenile system may not provide the intensive therapy the teen could receive at a $450,000-a-year rehab center the parents would pay for.