Japan is known for having one of the world’s most efficient and comprehensive public transport systems, but it’s also a nation of drivers and car-lovers, with nearly 80 million vehicles on the road. Now, as one of the planet’s most aged nations, with one in five citizens aged 70 or older, it is facing a sensitive problem: how do you keep traffic accidents down as people get older?

It’s an important question: last year in Japan the proportion of fatal traffic accidents caused by drivers 75 or older rose to 14.8%, up from 8.7% in 2008. And although last year overall traffic deaths in Japan were the lowest since 1948, over-65s made up a record high of 56% of the total deaths that did occur.

According to a Japanese government report in June, drivers 75 or older caused more than double the number of fatal accidents in 2018 than younger drivers did. More specifically, the over-75s caused 8.2 fatal crashes per every 100,000 on the road, “about 2.4 times the number caused by those aged 74 or younger”.

Deadly accidents involving older drivers continue to make national news. Right now in Japan, over-75s must take a cognitive test every three years before they can successfully get their licence renewed, and proposals over the summer aim to allow elders to only drive cars with advanced automatic braking systems.

Yet despite unilateral safety efforts, the biggest issue remains that there’s no one-size-fits-all solution to keeping elders driving safely. That’s because not every human at the same age or life stage is going to be the same. “You can’t say at X point in someone’s chronological age, they are likely to experience specific declines,” says Alana Officer, a disability and rehabilitation coordinator at the World Health Organization.

Plus, some studies show that the youngest drivers are more dangerous than the eldest; that same Japanese government report from June found that drivers aged 16 to 19 were the most dangerous group, causing 11.1 fatal accidents per every 100,000 licenced drivers. What’s more, the higher risk of elders dying in a car crash could also be due to increased age-related susceptibility to medical complications.

Officer says that if you have policy that is strictly tied to age – perhaps revoking licences for all people over a certain age in the name of public safety – you run the risk of ageist laws that discriminate.

So what can be done and what is Japan doing? The answers aren’t clear cut, but a mix of mindful policy and new technologies may indicate a path for the future.