WHITTIER, Calif. (KABC) --New questions swirl around the death of a student with autism who was left on a school bus.
For five months, the Whittier School District and Pupil Transportation Cooperative have been reviewing safety measures after 19-year-old Paul Lee was forgotten on board his school bus.
Lee was so disabled he didn't know how to call out for help on the sweltering hot day in September 2015.
For five months, both the school district and PTC have declined to accept responsibility, infuriating parents of Whittier's students with special needs who have been lobbying for a high tech tracking system.
"When my son is late, I think about Paul and I think about how long am I waiting for. Where is my son at? Is he alone on the bus? Am I waiting too long?" parent Mary Ellen De La Vega said.
A lawsuit filed by the Lee family has turned a corner. In a discovery document, PTC admitted the conduct of its driver was a cause of the death of the decedent and that PTC is vicariously liable.
"They admit they were a cause in the death of Paul and that's undisputed and they can't take that back and they won't take that back," Rahul Ravipudi, lawyer for the Lee family, said.
But also in the documents, the bus company stated the school district shares responsibility because they knew of Paul's limitations.
"They needed to receive him at the bus stop," Ravipudi explained.
De La Vega said she found a tech company that would offer PTC a grant for ZONAR, which tracks each bus and student with GPS. She said the co-ops board rejected the offer.
On Wednesday, a PTC spokesperson said a smaller scale check system is being installed in which the bus operator must swipe a device in the back of each bus to ensure it's been cleared. While the lawsuit plays out, the investigation into potential criminal charges has been put on hold.
Whittier police said the coroner's report has not been finalized and until it is complete, police cannot make a determination on any potential criminal charges.
The bus cooperative released the following statement to ABC7:
"We're still in active litigation, so we are limited on what we can say. However, the PTC community continues to mourn the loss of our student Paul Lee. The safety of students continues to be our top priority. As such, we are adjusting our systems and protocols to ensure something like this never happens again.
While the Zonar tech company encouraged PTC to purchase their product, due to timeliness, PTC chose to move aggressively first with the Child Check-Mate System."