Madeleine McCann’s parents checked on her every half-hour while she slept in her room at an Algarve resort – yet still she was abducted. What is the law in relation to leaving children alone? Professor Carolyn Hamilton offers her legal opinion and two Times writers give their own experiences as mothers

Scenario 1: You have three children under 5. You go shopping at the supermarket for 20 minutes, leaving them asleep in their car seats with the doors unlocked to avoid their movements triggering the car alarm.

This scenario is not advisable. It is an offence under section 1 of the Children and Young Persons Act 1933 to neglect or abandon a child under the age of 16 for whom a parent or carer has responsibility, but the law gives no detail of what amounts to neglect or abandonment. Prosecution and/or conviction depend largely on the circumstances. The punishment can range from a fine to ten years’ imprisonment.

The court is to likely to take into account the age and maturity of the child, for how long he or she was left alone and the arrangements to ensure his or her safety. Here, the children might get out of the car and wander on to the road – or anybody could remove a child from the car.

If the car doors were locked the children might be safer, but then what might happen if the children became very distressed in an enclosed space? Technically, children should not be left alone like that until they are 16. Five minutes might be acceptable in a locked car; 20 minutes is too long.

Scenario 2: You have 18-month old twins. You put them down for their afternoon nap in their cots, then dash down the road to get a pint of milk for a cup of tea. You are gone for less than ten minutes.

In this scenario, if the twins were asleep in cots and couldn’t get out, a parent might reasonably decide to leave them. If they were able to walk about – for instance, leaving a child of 6 awake and alone at home for ten minutes – it would be more problematic. You would need to worry not only about intruders but also about accidents; the possibility of a child burning some toast, for example, and starting a fire.

For a child of about 12 and above, it would depend largely on his or her maturity and factors such as whether he or she had been left at home alone before. Obviously it would be much better to have neighbours who could check up, and doors should be locked. I would never recommend leaving a child of any age for very long, but for children in cots, ten minutes is probably safe enough. I wouldn’t say this situation is desirable but it’s better than scenarios 1 and 3.

Scenario 3:You have three children aged 10, 8 and 6. You go out for dinner, leaving them in bed at home. You tell the eldest to ring you on your mobile if there are any problems.

This would be a real matter for concern. If the parents were out for dinner, they might easily be gone for a few hours. Even if this was for lunch and not for dinner (so in the middle of the day) it would still be highly undesirable.

If they were very close by and checking on the children often, the situation would be different – but leaving three children of that age alone for several hours would still be extremely unadvisable, as the potential risks are simply too great unless you can come back and check on them often.

Even if the eldest child could be relied on to use the phone, if the parent could not get back within 15 minutes there is a possibility that he or she might be charged with abandonment.

If a neighbour was there in case of emergency it would certainly be better, but because of the length of time involved it would still be very ill-advised.

Scenario 4:You go out for dinner in a hotel complex on holiday abroad, leaving a child aged 3 and twins aged 18 months in a locked room. You return to check on them every half hour.

If the parents have taken all the risks into account and decided that it is safe to leave the children, this would probably be reasonable. If the children were awake or a bit older and able to wander around, or potentially even to open the door to an intruder, perhaps not. But asleep, with the door locked and people constantly checking up on them, it is likely to be reasonable.

You should be checking on them very regularly. I don’t think it’s any less safe in Continental Europe than it is here. Leaving children alone in this manner is not desirable, but parents have to balance the demands of life and will probably have to consider such issues regularly.

A parent needs to ensure that children are safe if they are left alone. Leaving them for a short while, asleep, in a locked room with regular checks is acceptable. Leaving them for two hours, or with unlocked doors, is not.

MARY ANN SIEGHART: Your children are 20 times more likely to be killed by lightning than to be abducted by a stranger. You are much more likely to get five out of six numbers right in the National Lottery. Yet “It could be you” is the dread thought that all we parents have had since hearing the news that a three-year-old girl had been snatched from her hotel room in an Algarve resort.

How should we react? How protective should we be? The least we can do is try to match our behaviour towards our children with the real – rather than the imagined – risks that they face.

If we were rational, we would make much more fuss about them playing in the park and sheltering under a tree during a storm than talking to strangers. If we were rational, we would be more worried about them dying from a wasp, bee or hornet sting than from a paedophile murder. And we wouldn’t let them anywhere near a bicycle.

In our family, we have always been pretty robust about children’s safety. Our general view is that oversheltering does them no favours.

If they never learn to cross the road as a child, they are more likely to be run over as a teenager. If we don’t teach them to be streetwise, they won’t cope when – and there has to be a when – they are out on their own. For dependent children have to grow up into independent adults. There is no way of avoiding that. The best we can do is to prepare them for independent living. And that means gradually increasing the amount of freedom and responsibility that we give them.

When our elder daughter was 5, we let her walk round the block to the sweet shop. It didn’t involve crossing any roads, and she knew not to walk into the street or to get into a car with a stranger.

Unbeknown to her, my husband followed her the first few times at a distance. She was fine, and was generally rewarded with a free sweetie from the kindly shop owner, which allowed her to learn that other adults outside the family could be trusted to keep an eye on her, too.

By the time our children were 9 and 7 we were letting them go for walks and bike rides (wearing cycle helmets) together in the countryside. They learnt to rely on each other and to take note of their surroundings rather than following a parent blindly.

At 11, our elder daughter was walking to school and back, a mile each way, every day. And last Friday our younger daughter, now 13, made it from Winchester to Norwich on her own, a journey involving four trains and a crossing of London. All this – we hope – will encourage self-confi-dence and self-reliance.

You have to make them aware of the risks and teach them how to deal with them. Both our daughters have been on a self-defence course but, equally, neither is shy of asking a friendly-looking adult (ideally a woman) for help if necessary.

They know that abductions happen but they also understand that the reason why the occasional child-snatching fills so many acres of newsprint is precisely because it is so very, very rare.

Of course we parents all worry about our children. Yet childhood is the safest part of a person’s life and is becoming ever safer. You are least likely to be murdered between the ages of 5 and 16, and if you are, the killer is likely to be someone you know – possibly even your parent.

What is more, child deaths from any cause in this country have more than halved in the past 25 years.

The world isn’t getting more dangerous for them. It’s just that parents are getting more neurotic.

SARAH VINE: I am living proof that it is perfectly safe to leave your children at home alone. From a relatively young age (7 or 8, if memory serves), my parents used to leave my brother and me in the house at night while they popped out for a bite to eat. No harm ever came to us, principally because they always took precautions to make sure that we were fundamentally safe (locked doors and windows, watchful neighbours, etc), but also because, thanks to their trust, I was a sensible little girl.

You might have thought, then, that I would be similarly disposed towards my children. But no. It anything I am even more neurotic than most about leaving them alone. In the evenings, when they are asleep upstairs, I will not even go as far as the bottom of the garden (where I have my home office) for fear that something might happen while I am out of earshot. If I fill up the car with petrol with them in the back, I will drive to the front of the forecourt to pay, just so that I can keep an eye on them.

Ridiculous behaviour, of course, but I cannot seem to help myself. In my defence, both my children are under 4: they are small, trusting and extremely accident-prone. Only the other day I caught my daughter sitting in her Wendy house with a plastic bag “hat” on her head – this despite the fact that all plastic bags in our house are meticulously knotted and put away safely.

But there are other reasons. First, I am older than my parents were when they had me – much older. And the older you get, the more risk-averse you become: too many scare stories, too many chilling news reports (and, it has to be said, a few nasty experiences of my own). They were 21 when they had me: barely out of nappies themselves. I was 36 when I had my daughter: an entirely different proposition. If life teaches you anything, it is that not everybody is as good as they ought to be. I know we are all supposed to rail against our risk-averse society, but when it comes to your children, it’s hard.

There is another factor, too. Being left alone in the house was scary. I never let on to my parents how scary, as I didn’t want to disappoint them. But I was pretty terrified. I would lie in bed, wide awake, listening to the strange noises of the night, analysing every squeak and rustle, until I heard the welcome crunch of their car’s tyres on the driveway – at which point I would finally succumb to sleep.

So I agree: we should not cocoon our children. But nor, by the same token, should we assume that the process of growing up is always an easy one.