Video footage obtained by police shows the 61-year-old travelling closely behind a Suzuki Swift as he drove onto the bridge from Victoria St.
He then accelerated to overtake the car, using the left lane, and then quickly changing back into the right-hand lane to get in front of the Swift.
As Napier sped across the bridge, Li was trying to cross the eastbound lanes towards a pedestrian island in the middle of the road.
After successfully crossing the first lane, she was suddenly struck by Napier’s ute in the second lane.
The impact saw her body thrown for 24 metres before landing on the left-hand lane.
The traffic flow was moderate to heavy at the time.
When questioned by police, Napier said he was travelling between 60kph and 70kph, which was consistent with CCTV footage obtained by police.
Napier said Li stopped in the middle of the two eastbound lanes and he accelerated to get past her but she stepped out in front of him and he hit her.
Before his guilty plea, he had been defending the charge and was due to go to trial in September.
However, Napier was today convicted by Judge Marshall and remanded on bail for sentencing in July.
Belinda Feek is an Open Justice reporter based in Waikato. She has worked at NZME for nine years and been a journalist for 20.