Lepper was in the eastbound lanes when she was shot in the head. She then lost control of her gray 2004 Chrysler Sebring, drifted into the far right-hand lanes and slammed into a wall.
Someone driving on the freeway saw the accident and called 911, but didn't know Lepper had been shot. The witness thought the woman had just lost control of her car.
"Somebody stopped to render assistance to the victim, but we do not have a witness to the shooting," said Capt. Bill Siegl, CHP.
Lepper was the only person inside the vehicle as the time of the shooting.
When CHP officers arrived at the scene they noticed that the driver's side window was shattered and realized Lepper had been shot in the head. They tried to revive her at the scene and she was transported to Pomona Valley Hospital.p> Lepper was pronounced dead at the hospital around 12:30 a.m.
The CHP shut down the freeway until about 2:30 a.m. while officers combed the freeway, trying to find any clues.
Family members say that Lepper had worked at Rios Chiropractic in Pomona, but was starting a new career. Her sister says that Deborah was a giving, loving woman who was known for helping at risk kids in her hometown of Pomona.
Lepper's family and the CHP hope that someone has information that will lead them to the person who pulled the trigger.
"We are seeking the public's assistance in this case. We are asking that anyone with any information -- that saw anything at all on the freeway -- to contact us," Capt. Siegl.
Anyone with any information regarding the shooting is asked to call the California Highway Patrol at (800) 835-5247.
Eyewitness News Reporters Melissa MacBride and Wendy Burch contributed to this report.