A teenage girl says she yelled at a driver to slow down and move over right before the car crashed into her mother, who was riding a horse.
Peng Wang faces a charge of careless driving causing injury for hitting Karen Rutherford while she and her daughter were riding in Dairy Flat, Auckland last August.
Ms Rutherford suffered multiple injuries. The horse, named Curious George, died.
In a judge-alone trial, which started in the North Shore District Court today, Ms Rutherford's 13-year-old daughter, Ella, said they saw the car come over the hill at speed.
She said she and her mother yelled at the car to slow down and move over because he was coming towards them alongside markings at the edge of the road.
"It seemed like he was travelling really fast. Ninety-nine percent of people slow right down and move over when they see us on the horses, but this car didn't," Miss Rutherford said.
She said the car skimmed the whip she was holding. She then heard a loud crash.
She told the court she turned around and saw debris fly, before noticing the injured horse and her mother lying in the gutter.
"I went over to George, he was struggling to get up - I looked down and noticed his leg was snapped.
"Mum was lying in the ditch not moving and I was scared [because] I thought she wasn't alive - but a man that came to help said she was, so it was a huge relief."
In giving evidence in the trial, Ms Rutherford broke down as she spoke about the accident.
"I was lucky not to lose my leg, I had multiple broken bones. I am still suffering, I can't focus for longer than four hours a day, my eyes begin to shut and I get tired."
She said she also saw the car coming down the hill "like a bat out of hell - it was like he was intent on hitting us".
"He was so far over right up against the white line, I was not scared because I thought he would move over, but he didn't."
She said the horse was not spooked and did not jump, but may have turned his head ever so slightly to see what was coming.
"The next thing I knew there was a flash of light, there was metal flying everywhere and I was in the air," Ms Rutherford said.
Ms Rutherford said the whole incident has had a huge impact on her family.
"We leased George for two years but he was a part of our family, he was such a gentle horse.
"Because this happened in our care we paid for the vet bills and paid the owner for him."
She told the court she was due to open a new business just two days after the crash, which had to be postponed.
"My husband was looking after our children and running to and from the hospital to care for me - this whole thing has cost us a lot financially."
Keiko Fegan, who was driving on the opposite side of road at the time, told the court she moved as far over in her lane as she could to give the driver - a Chinese national - space.
"I did that so he could move over and give the horses room, but he didn't, and he didn't slow down like I had."
Defence lawyer Tiffany Cooper asked Ms Fegan if the horse had got a fright and moved into the path of the oncoming car.
"I noticed both of them tried to move over to avoid the car. The second horse was wider - a bigger horse - so he was out further.
"I think it may have twisted or moved its head to the side just before it was hit."
Three more witnesses are expected to give evidence in the trial.