Transcript for Inside the Manhunt for the 'Affluenza' Teen
badly. Most wanted teenager in the country Ethan crouch escaped with just probation after killing four while driving drunk. He is being sur sued by the FBI and U.S. Marshals and Matt Gutman has the latest. Reporter: Investigators telling ABC news the teen fugitive infamous for that so-called affluenza defense in court may have a huge head start on authorities. I believe they planned in time their getaway to give them the maximum amount of time to be gone before we started looking for them. Reporter: ABC news learning investigators are tracking the family's phones, financial records and possible passports. Concerned the teen has fled the country. With the amount of wealth that these people have, there's a tremendous amount of different ways they could have gotten away, charter a boat, a plane. Reporter: In 2013 the then 16-year-old loaded himself with booze and his truck with friends, he pleaded guilty to killing four in this horrific drunk driving crash. His sentence, ten years' probation and zero jail time. His legal team argued he suffered from affluenza. That he was too spoiled to know right from wrong. Investigators say shortly after this video was posted to Twitter, purportedly showing him at a boozy party, couch vanished. Now on the run authorities believe with his mother. Do you recall ever disciplining Ethan for anything? Sometimes I would take little things away from him or we would just discuss the problems. Reporter: But now his mother may be the one to suffer consequences. It is a felony to aid and abet a fugitive and the sheriff tells us if there's any way to prosecute her they will. Ethan couch because he's still considered a juvenile under the law he's unlikely to face any jail time if apprehended. Hard to believe, okay, Matt Gutman, thanks very much.
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