Once upon a time children would enjoy cramming sardine-like into the back seat of the family car. Curling up in the footwell or lying flat across crunched-up friends added to the fun and games. The loser would usually end up in the middle.

But the fun disguised a steadily rising death toll among children as roads became more crowded and traffic speeds increased. On average, children are killed or seriously injured in car crashes at the rate of about two a day.

An unrestrained child in a 30mph crash is propelled with a force 30-60 times their body weight, almost certainly injuring themselves and others in the vehicle. What is surprising, however, is that it is not illegal to have an unrestrained child in the car.

As the law stands, the driver is required to put a child in a child restraint (ie, a child seat or adult seatbelt used with a booster) only where “an appropriate one is available”. Otherwise children under three can legally sit unrestrained in the back seat (although not in the front). And children aged three and over can sit in the front or rear seats using an adult seatbelt where no suitable child restraint is available.

Until the child passes its 14th birthday, it is up to the driver to make sure they buckle up. After that, it’s up to the teenager.

If these laws seem insufficient, even careless, it’s worth remembering that when they came into force in 1989 seatbelts had been compulsory for drivers and front-seat passengers for only six years, though parents always have a responsibility for their children and can be prosecuted if they are negligent or reckless.

In June Corinne Burgwin, 24, of East Grinstead, West Sussex, was found guilty of causing death by dangerous driving after her six-month-old daughter Elisha suffered fatal chest injuries due to a badly secured baby seat. Although designed to be rear-facing, the seat had been placed facing forwards on the back seat with the harness not properly tightened.

In future all parents will have to take more care. From May next year a European directive is expected to come into force making it illegal to take children in cars without an appropriate child restraint until they reach 12 years old or are taller than 4ft 5in.

From May 2008 all seats would then have to adhere to stiff United Nations design and performance standards. And from May 2009 it will be illegal to carry more passengers than there are child restraints or seatbelts — which some campaigners fear will mean more cars outside the school gates and a logistical nightmare for time-strapped parents trying to get children to and from dance classes and sports matches.

The Department for Transport is considering an exemption for “short, occasional trips”, although it is unclear what this would include. The rules will not apply to taxis.

Child safety is one area where parents are ahead of the letter of the law in many respects, and manufacturers have responded to government safety advice by producing a wide range of safety equipment. Such a wide range, in fact, that it is often bewildering.

Child car seats are divided into five groups, each relating to different weights. The first is group 0, suitable for babies up to 22lb or about nine months, followed by group 0+, suitable from birth to about 29lb or roughly 15 months. Babies up to this weight are best travelling in rear- facing seats or cradles. If the seat or cradle is in the front the passenger airbag must, say safety experts, be disabled. From next May this is expected to be law.

Some models of car will allow you to do this with a special key but for others it will involve a trip to the dealer. Mercedes produces child seats that include a microchip that can be read by a transponder in the front seat and will automatically switch off the front airbag. Prices start from £150. The seats should work in all Mercedes cars produced in the past five years.