The Texas teenager who used an "affluenza" defense in a deadly drunken-driving wreck is expected to waive all detention hearings and stay in jail until turning 19 next month, a strategy that may be aimed at keeping him out of jail as his adult probation begins.

Ethan Couch waived his right to a Friday hearing, and the Tarrant County District Attorney's office said "all signs point" to him waiving the rest of his juvenile hearings.

A judge sent Couch to adult court in February. His case will officially transfer on his April 11 birthday.

Couch could face up to 120 days in jail under adult probation. He won't receive credit for what he's serving, but experts say a judge will consider the time, which may be why he's waiving hearings.