Texas prosecutors asked a judge on Tuesday to move to adult court the case of a teenager given probation in juvenile court for killing four people while driving drunk, a sentence critics say was too lenient and influenced by the family's wealth.

Ethan Couch, derided for an "affluenza" defense for the 2013 fatal crash, fled to Mexico in December with his mother in likely violation of the probation deal that kept him out of prison after being convicted in juvenile court of four counts of intoxication manslaughter.

Lawyers for Couch, who is being held at an immigration detention facility in Mexico, want the proceedings in Fort Worth to come to a halt, arguing the case should not go forward because their client is not there.

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Tarrant County prosecutors contended Couch is responsible for his own absence by fleeing to Mexico and fighting his deportation.

If Couch is found to have violated his probation and his case in transferred, he could face about four months in an adult prison. Another probation violation could bring up to 40 years in prison, legal sources said.

Couch was 16 when he was tried in 2013 with a psychiatrist testifying the boy had "affluenza" and his family's wealth had left him so spoiled that it impaired his judgment to tell right from wrong.

The affluenza diagnosis, which is not recognized by the American Psychiatric Association, was widely ridiculed.

Couch and his mother, Tonya Couch, 48, fled to Mexico in early December after a social media video emerged showing him in possible violation of his probation by being at an alcohol-laden party.

Mother and son drove a pickup truck to Puerto Vallarta shortly after that, where they were caught by Mexican authorities after a manhunt lasting more than two weeks.

Tonya Couch was charged this month in Tarrant County with a third-degree felony for helping her son flee. She faces up to 10 years in prison if convicted.