Ethan Couch made headlines in 2013 after avoiding jail time despite being convicted of DUI manslaughter thanks to a defense that his wealth and privilege prevented him from seeing right from wrong.
He made headlines again in recent weeks after video surfaced that appeared to show the 18-year-old playing beer pong and violating his probation.
Couch has been a fugitive since he missed a Dec. 11 hearing set to address the matter. Last week, the U.S. Marshals joined the search for the teen, who they believe may be with his mother.
"If we [had] a top 10 wanted list today, he's number one," Tarrant County Sheriff Dee Anderson told ABC News.
Anderson told INSIDE EDITION: "My biggest fear is that they have gone somewhere where we are not going to find them at all."
Authorities have been unable to contact Couch and his mother Tonya since he missed the appointment with his probation officer near Fort Worth.
"I said then that we should have him in jail, he should not be out there walking the streets. I hate to say I told you so but I told you so," the sheriff said.
Many are also asking what role the mom is playing in the disappearance and fear the two may have fled the country.
An article in the Dallas magazine, D, earlier this year painted a bizarre picture of the mother-son relationship.
The founder of a school Ethan attended said of Tonya: "She loved the boy so much that she couldn't say no to him."
The psychiatrist who came up with the phrase "Affluenza" at Ethan's DUIsentencing in 2013 said Tonya was "addicted to the kid."
The rented house where Ethan and his mom lived for a year right before they disappeared has a modest kitchen and the bathroom and is reminiscent of a motel.
When police arrived there after Couch failed to appear, they found it completely empty save for a pinball machine, according to the New York Daily News.
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