Exams have finished, school's out and university students are home on holiday. Time for a celebration with our mates before the holiday job starts - except that it should not involve a group of young people AND a car.
Last year about this time, a 17-year-old Whangārei girl died and three other young people were injured after a car rolled off the road and into a paddock at about 9.15pm on a Friday night.
The driver was airlifted to Auckland Hospital in a serious condition. He was my grandson's friend and he is still struggling to get back to normal, some 12 months later.
There are several research reports emerging about teen drivers which must make their parents pause before they lend the family car.
One study in the US identified that, compared to driving with no passengers, a teenage driver's risk of death per mile - doubles when carrying two passengers aged under 21, and quadruples, when carrying three or more passengers that age.
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Young drivers with passengers have a tendency to show off - they take higher risks when surrounded by their peers.
A few years ago, the psychology department at Temple University in Philadelphia used a simulated driving test with teenagers, testing their behaviour at yellow traffic lights both when their friends were watching them and when they were not.
The outcome is unsurprising. Adolescents were much more likely to red light run when their friends were watching.
The researchers conducted brain imaging tests and found that the challenge activated the drivers brain reward centre when they were being observed, as compared to when driving alone. In this case, the balance in the brain between risk and reward becomes unbalanced if the driver is showing off to their mates.
This is not a particularly new phenomenon. I'm sure that many of us boomers can remember the same challenge when we were behind the wheel with a bunch of mates.
We just understand it a bit better now, and appreciate the consequences. There but for the grace of God go I.
The human brain is made up of a number of lobes which control different functions. The frontal lobe deals with judgment and decision making and is the last part of the brain to develop.
The parts of the brain which control muscle movement and balance, interpret sound and visual information and which manage together all these senses, are well developed at driving age.
Those skills are there in young drivers, but the part dealing with perception, judgment, decision making and balancing risk and reward takes longer to develop - up to age 25 in some cases, so that driving has not yet become an automatic task.
Most adults can relate to driving on "autopilot" at some time or other. That is driving on instinct within the law based on our experience. We may not remember the speed limit sign or the traffic lights we have been through but we are still able to react to sudden or unexpected events.
Young drivers' brains are not yet able to do this, driving has not yet become automatic. The risk/reward balance is not yet instinctive and the presence of mates in the car leads to the potential for taking bigger risks with no balancing perception of the consequences.
So, for a young person in a car, it is not just about making sure you have a designated sober driver, but understanding, as well, that the rewards of risky driving behaviour are momentary but the outcome could be life long.
Parents. No matter how much you trust your teenager, or how good a driver you believe them to be, be wary of lending the family car for the end of exams celebration.
• John Williamson is chairman of Roadsafe Northland and Northland Road Safety Trust, a former national councillor for NZ Automobile Association and former Whangārei District Council member.