Jackson Williams, 17, was killed a year ago in a car crash. She can't cope with the "feeling of wet grass on her ankles" because it brings back memories of running to her unconscious son on a local oval surrounded by ambulances and strangers on that damp winter's night a year ago, she told Fairfax Media. And she can't stand the smell of apple shampoo because it reminds her of the smell of Jackson's hair as she cradled him for the last time in the ambulance. "It takes me back to that night," the Central Coast woman told Fairfax on Friday. "I can see his ear leaking blood," she said. "It fills me with horror, and overwhelming pain and hopelessness come flooding back." On Friday – a year and four days after Jackson died – she couldn't attend the sentencing of the driver of the vehicle because it hurt too much.

The car crashed into a telegraph pole on Willoughby Road, Wamberal. Credit:digicrew The driver – who had his Ps for just over two weeks – was convicted of dangerous driving occasioning death. He was sentenced to 200 hours of community service, and his licence was suspended for three years. He can't be identified because he was a minor at the time of the crash. Handing down the sentence, Magistrate Louise McManus of the Woy Woy Children's Court said the boy, who was of good character with no prior crimes, would always have to live with the pain of losing his friend. Jackson Williams with his mother Michelle. Credit:Michelle Williams She urged him to use his experience to remind other young drivers "to not use a car as a toy".

The closed court room heard that none of the five teenagers – two 17-year-olds and three 16-year-olds – in the car had been drinking or taking drugs. The driver had not been speeding or reckless. Jackson Williams took this moody shot of Terrigal and its landmark the Skillion on the night he died in a crash. Credit:Jackson Williams Getting airborne on the Dipper The night of the crash had been one of innocence: the group of five friends stopped for ice cream at Terrigal where Jackson, a serious photographer, took moody photos. As they were heading home about 9pm, the driver was urged by the passengers to drive over the Willoughby Road culvert covering a storm water drain.

Jackson Williams and friends hanging out a local Central Coast beach. Credit:Jackson Williams It was a well-known spot because it caused "a sensation in their stomachs ... due to the steepness of the dip", said the agreed statement of facts heard by the court. Although the driver of the car was urged to speed up, he drove carefully through the culvert, a 25 km/h zone, braking the first time so nobody experienced the sensation they sought. Lindy Hewett at the crash site where residents have been lobbying for road improvements. Credit:Louise Kennerley He was urged to do it again. One of the passengers urged, "go fast, go fast", the court heard.

"Coming to the top of the dip, we were going so fast that the car sort of lifted up and dropped down into the dip, and then coming to the top of the dip, we definitely got air," one of the passengers said, according to the statement of facts read in court. The telegraph pole where the car carrying five friends crashed, killing Jackson Williams, 17. Credit:Louise Kennerley The result of the young driver's choice to turn around had "catastrophic" consequences for the people in the car and him, said the magistrate in her ruling. The driver's solicitor Phil Carey of Nowra told the court it was the "failure of an inexperienced driver to judge an appropriate speed for the conditions". The scene of the accident where Jackson died. Credit:digicrew

The P-plate driver hadn't been speeding or driving recklessly at any other time that night. But this time the inexperienced driver – who had only driven the second-hand manual Forrester he'd been given two weeks earlier once or twice without adult supervision – crossed the culvert too fast for the conditions, especially given it had been raining and the vehicle had worn tyres. The vehicle was out of control for 80 metres before crashing heavily with a telegraph pole. Selfie: Jackson was a keen magician. Credit:Jackson Williams Jackson died at the scene. All four survivors were hospitalised. A 16-year-old boy was airlifted to hospital because of serious injuries. The Jekyll and Hyde moment when safe L drivers get their P-plates

So far this year 18 young drivers aged 17-25 have been killed in crashes in NSW, compared to 87 drivers in all other age groups. This compares to 23 young drivers killed in the same period last year. Research shows the first month of driving with P-plates is the riskiest time, compared to L-plate drivers who are among the safest driving under adult supervision. The first comprehensive review of recent data published a week ago shows Australia's graduated driving licence system has reduced deaths, crashes and injuries. P1 drivers – the first stage of NSW provisional drivers licensing system after L-plates – represent 3 per cent of the 6 million drivers on NSW roads, as of June 2017, but they represent more than 20 per cent of all fatalities. With each additional passenger of a similar age in the car, the crash risk increases for young drivers.

Ms Williams called for changes to NSW's graduated driving licence system that would ban large groups of teenagers from riding in cars together. She wants the existing 11pm to 5am limit (restricting P1 drivers in NSW and QLD to only one passenger under 21) to be extended across 24 hours. Victoria and other jurisdictions around the world already have this rule. Some places ban P-platers from driving at night. "I would only have one other person in the vehicle 24 hours a day," Ms Williams said. She would also like each young driver to do an advanced driving course. Ms Williams knows the road rules: she used to work for Service NSW, but had to leave after Jackson's death because it was heartbreaking to see other young people get their Ps and take it so lightly. It also "sickened her" to see people who had broken the law getting their licences back. On the night of the crash, she went to bed shortly before 9pm reassured that the nighttime restriction on passengers meant Jackson would be home soon.

If the passenger rule was extended to 24 hours, research shows the risk of such a crash would have been reduced. Associate Professor Teresa Senserrick, the author of last week's review, backed a 24-hour passenger limit. "Of all the results, it was the night passenger restrictions that seemed to come up with the most positive findings," said Associate Professor Senserrick, an expert on novice drivers with the University of NSW's Transport and Road Safety (TARS) Centre. If this passenger restriction (except for a parent or professional instructor) was in place 24-hours-a-day and night driving for P1 drivers was banned it could lead to a 20 per cent reduction of fatal crashes among provisional drivers and a 40 to 50 per cent reduction in all night crashes, the report said. Banning all P-plate drivers from carrying any friends or "peer passengers" in the first months of a P licence would lead to an additional 25 per cent reduction in crashes.

South Australia bans young drivers from carrying more than one passenger under 21 at any time of the day, and also bans red P-platers from driving between 11pm and 5am. Victoria allows only one passenger under 21 at all times of day. Professor Senserrick said the evaluation of Queensland's graduated drivers' licensing system - nearly identical to NSW's - provided evidence for the first time that Australia's unique regime of requiring L-plate drivers to chalk up 100 or 120 hours behind the wheel was a success. Researchers compared crash and injury rates of young and novice drivers in Queensland and their passengers from July 1999 to June 2012, comparing the new system with the old that ended in June 2009. Some critics had suggested that requiring learners to spend more hours on the road would increase crash rates. But on nearly every measure, young drivers were safer than in the past, particularly in the danger month after they first got their Ps, said Professor Senserrick.

NSW will consider a 24-hour restriction on P-platers' passengers The director of the NSW Centre for Road Safety Bernard Carlon said NSW's graduated licensing system had been extremely successful since its introduction in July 2000, and flagged further changes, including the extension of the night time limit of one peer passenger. In the year before NSW system was introduced, 204 people died from crashes involving a driver aged 17 to 25 years. In contrast, last year 99 people died in young driver crashes. "Although it is still 99 too many, it represents a 51 per cent reduction in fatalities," Mr Carlon said.

The government would consider the introduction of 24-hours restrictions on the number of passengers under 21 as part of its Future Road Safety Transport Plan, he said, but it would need to take into account its impact on rural and regional drivers. Mr Carlon said from November 20, NSW would require learner drivers to take the Hazard Perception test before they can progress to a Provisional P1 licence. The test is currently a requirement for Provisional P1 drivers to progress to a Provisional P2 licence. Professor Senserrick said Australia's graduated driving system was trying to protect young and inexperienced drivers at the time when they were most at risk. "For all drivers, driving at night is a higher crash risk. But for young ones, the peer passenger restrictions are in place because it really only seems to be with young people that lots of passengers increases their risk." It was much harder for a young person to tell everyone to "shut up for a second".

American research has also found that most young drivers are capable of driving safely with an adult in the car. Yet these same safe drivers will alter their driving if they have passengers who they perceive like risky behaviour. Although she wouldn't comment on the details of the Central Coast crash, Professor Senserrick said young people's brains were wired differently from an adult's. They found it hard to tune out distraction, particularly by their friends. "So when you have passengers in the car, there is the distraction of looking at them, particularly if they are in the back seat and you are looking away from the roadway." Overwhelming anger after that fatal starry night Ms Williams told Fairfax this week that some days she had so much anger it was overwhelming.

She said she thought the driver's sentence was light and did not reflect the crime. "Jackson is dead and if it wasn't for one stupid choice that night he would be living the life I had wanted for him. On the other hand if the driver had been given a custodial sentence I would have been devastated for him and his family. The court played no role in handing him the hardest sentence of all – living with fact that you killed your mate. It is just so shattering and heartbreaking for so many." Jackson – a popular and capable student and soccer player – was only a few weeks away from getting his P-plates, but that night his life was ended by one mistake by his friend. "These kids weren't into drugs, they weren't into alcohol and they were sporty, and they all come from fantastic families that nurtured them." She had known the driver since he was a boy. "He never intended to do what he did, and he has to live with the consequences. But we have also had a horrible sentence as a family."

On the night of the accident, Jackson stopped at Terrigal's famous landmark, the Skillion, and took a moody night photo. It now hangs on the wall of the family's home, an eerie reminder of that fatal starry night. "They were just hanging together, they would have been singing in the car, they were just 17-year-olds mucking about in the car, and cruising. There was nothing sinister about them," she said. The culvert which the teens drove over has been a favourite spot for generations, and residents like Lindy Hewett have been lobbying for it to get fixed.

Like many of his generation, Jackson's distraught father Mark Williams remembered going there as a teen. When the surf was flat, his mater would get airborne by flying over the culvert. Everyone his age remembered this part of the road, he told Fairfax outside the court, and there had been identical crashes only a week before the crash that killed his son. "Within seven days, ten teenagers crashed at the same spot," Mr Williams said. Mr Williams has urged Gosford local member Liesl Tesch and federal member for Robertson, Lucy Wicks, to install speed humps before and after culvert. They would be the most effective way to prevent drivers from getting the " little rising belly feeling" that gave them a thrill, he said.

A petition started by Ms Hewett on Change.org backs the call for changes. The petition was presented to Parliament by Ms Wicks, who said this spot on Willoughby Road had been the scene of 20 incidences over the last decade, including 12 resulting in injuries and one fatality. She promised change: "While we know that this cannot be fixed overnight, my commitment is that I am certainly not going to rest until it is done and I know our community will not allow us to rest until it is done either," Ms Wicks said at the time. So far, though, no changes have been made, said Ms Hewett.