'Affluenza' teen Ethan Couch investigated after allegedly being seen in beer pong video
Ethan Couch (WFAA-TV)

Law enforcement authorities launched an investigation on Thursday into a video that allegedly shows the Texas teen from a wealthy family who killed four people while driving drunk among revelers at a party, possibly in violation of his probation.

The teen, tried in juvenile court, was spared prison but his sentence of 10 years probation for intoxication manslaughter prohibits him from drinking. A psychologist called as an expert witness by his lawyers said the teen had "affluenza," a condition where enormous wealth blinded him from being responsible for his actions.

The American Psychiatric Association does not recognize "affluenza" as a diagnosis. The probation sentence ignited a public backlash, with many saying family wealth helped shield the youth from more serious punishment.

"We are aware of it and are investigating the claims,” said Samantha Jordan, a spokeswoman for the Tarrant County District Attorney’s office.

The six-second video was posted on Twitter by a user on Wednesday. It shows a few people around a table covered with red plastic cups and cans of beer in a game of beer pong.

As a young man dives onto the table, the camera pans to show a male resembling the wealthy teen jumping and clapping at the sight.

A Twitter user who goes by the handle @BlondeSpectre wrote: "ya boy ... violating probation. i got more if u want."

The teen, who was 16 at the time of the deadly crash, had a blood-alcohol level that was nearly three times the legal limit when he was speeding and lost control of his pickup truck.

The truck struck the driver of a car that had broken down by the side of the road and three other people who had stopped to help the stranded motorist in June 2013.

Four other people were injured, two seriously, in the crash south of Fort Worth.

The teen, now 18, served time in a youth detention center but is no longer in custody, Jordan said.

The Tarrant County District Attorney’s office has begun the process of transferring supervision of the teen from juvenile to adult court. A hearing on the transfer is pending, Jordan said.

(Reporting by Marice Richter; Editing by Jon Herskovitz and Tom Brown)

Watch a report on the video, as aired on WFAA-TV, below.