DENVER -- Due to its complexity, the investigation into a fatal crash involving a suspected drunken teen driver will go to the Jefferson County grand jury, the district attorney's office said Monday.

District Attorney Scott Storey referred the case to the grand jury to "assist in further developing the investigation."

He said he believes the complex nature of the facts surrounding the crash that killed 17-year-old Samara Stricklen warrants the use of the grand jury to figure out what charges would be most appropriate.

Stricklen died on March 13 when a sport utility vehicle hit the car she was riding in head-on. Investigators said a 16-year-old girl driving the SUV was likely drunk at the time of the crash.

Toxicology test results were not released, but investigators said the level was sufficient to support a DUI charge.

The newly licensed driver was also carrying passengers in her vehicle, in violation of her driver's license restrictions. Drivers who get their license at 16 can't have additional juveniles in the car for six months.

A witness told 7NEWS that the teen girl who was allegedly behind the wheel at the time of the crash was actually in the back seat of the car 30 minutes before the crash occurred. The witness was not in the car when it crashed and said he couldn't say exactly who was driving at the time of the crash.

Lakewood police are aware of the witness, but they told 7NEWS they "have no doubt someone else may have been driving the SUV before the accident, but we have no doubt we have arrested the right person."

The district attorney's office wouldn't release further information about the case due to the protected nature of the grand jury proceedings.