MAYPORT, Fla. -

The driver of a car that hit and killed a teenager in October still hasn't been charged, and the family wants to know why.

Tyler Self (pictured below), 19, was struck and killed while walking on the sidewalk along Mayport Road at the intersection of Plaza Road.

Tyler's older brother, William Self, said he doesn't understand why the driver, 22-year-old Christopher Duboulay, hasn't been charged with Tyler's death, and the Florida Highway Patrol told him and Channel 4 that criminal charges are unlikely.

"They say he was killed instantly," Self said of his brother. "(Duboulay) didn't get any tickets, nothing that day. He walked away from it."

According to the a preliminary investigation report Tyler Self's family shared, Duboulay was tested for alcohol and drugs the day of the crash. It was only Tuesday that FHP shared the results with Self's family. The lead investigator said those results show Duboulay (pictured below) wasn't drunk or on drugs, and wasn't speeding.

William Self said he can't understand why it took more than six months to find out the results.

"I talked with the state this morning and they said they couldn't do anything because the state troopers weren't done with their investigation yet," Self said. "I talked with the state trooper 30 minutes later, and he said that they were done with their investigation and that there was nothing else they could do. I said, 'I wanted this man in jail.' He said it wasn't going to happen."

The FHP said investigations take time and a six-month time frame is not unusual. It said the investigators are also working on other cases at the same time, which can slow things down.

Duboulay recently pleaded guilty to possession of drug paraphernalia in an unrelated case.

The FHP said Duboulay probably won’t be charged with any criminal wrongdoing, but civil citations are still possible. The FHP said there was surveillance video of the crash which showed Duboulay was alone in the car.

The FHP said the final report is about to be submitted to the State Attorney’s Office, which will then decide what, if anything, to file in the case.