The defense attorney for a teenage driver accused of driving drunk while livestreaming the crash that killed her younger sister says a mechanical problem may have caused the accident in California.

The Merced Sun-Star reports Obdulia Sanchez's lawyer told a judge Friday that he has reason to believe the crash was caused by wear and tear on a tire, causing it to blow out.

Sanchez was driving a car that veered onto the shoulder of the road on July 21. Authorities said she overcorrected, causing the vehicle to swerve and overturn, ejecting and killing her 14-year-old sister.

Prosecutors said Sanchez was live-streaming on Instagram while driving and the video shows her taking her hands from the steering wheel.

Sanchez has pleaded not guilty to gross vehicular manslaughter and drunken driving.