'Affluenza' teen Ethan Couch could be moved to adult court now that he's back in Texas
Ethan Couch, known as the "affluenza" teen after he killed four people in a drunk driving incident in 2013, is seen at Mexico's National Institute of Migration before being driven to the international airport in this still image from a video provided by the Institute, in Mexico City, January 28, 2016. (REUTERS/National Institute of Migration/Handout via Reuters)

A hearing is planned on Friday to determine if the Texas teenager derided for an "affluenza" defense for killing four people while driving drunk will be moved from juvenile detention to an adult jail.

Ethan Couch, 18, arrived in Texas on Thursday after being deported from Mexico. Couch is scheduled to appear to before a juvenile court judge, who will decide where he will be detained.

His lawyers may try to have Couch sent to adult prison, where he can apply for bail, an option not available if he remains in juvenile custody. Couch faces a hearing on Feb. 19 to determine if his entire case will move to the adult system.

Couch fled to Mexico in December along with his mother after a video emerged on social media that likely showed the teen in violation of the probation deal reached in juvenile court that kept him out of prison for causing the deadly crash in 2013.

Couch was 16 when he was tried as a juvenile. A psychiatrist testifying on his behalf said he had "affluenza," as his family's wealth had left him so spoiled that it impaired his judgment to tell right from wrong.

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

If he is found to have violated the probation deal, Couch faces about four months behind bars. His mother, Tonya Couch, faces up to 10 years in prison for helping her son flee to Mexico.

Couch was sentenced in Tarrant County to 10 years of drug-and-alcohol-free probation for intoxication manslaughter, a punishment condemned by critics as privilege rewarded with leniency.

(Reporting by Marice Richter; Writing by Jon Herskovitz; Editing by Leslie Adler)