JONESBOROUGH, Tenn. -

A judge declared a mistrial in the case of Cody Dingus, who is charged with vehicular homicide following a 2012 Valentine's Day crash that killed his girlfriend, Sheridan Edwards.

Dingus testified in court Wednesday that Edwards grabbed the steering wheel and caused him to lose control on Knob Creek Road in Washington County, Tennessee, but prosecutors said the evidence showed otherwise.

News 5 has learned that a juror went out Wednesday night and drove the route where the crash happened, and shared that experience with his fellow jurors. The judge says he instructed them that they can only consider evidence used in the courtroom, and that is why he declared a mistrial.

Assistant district attorney Ken Baldwin says it's unfortunate for everyone involved to have to start over. "We're back to square one. That's the tragedy of this thing," he said. "This case is two and half years old. Both sides have spent an extraordinary amount of time and money. and many citizens have taken off work for three days. They had to interrupt their lives to be witnesses. All that is gone for now."

Prosecutors say Cody Dingus's blood alcohol level was three times the legal limit the night of the crash.

We're told it will now likely be November or December before the case is re-tried.