Claims are rejected, or subject to deductions, when the insurer considers that the policyholder is partly to blame.
An insurance policy is a contract that imposes rights and duties on both you and the insurer. You have a right to expect payment if the family silver is stolen - but you also have a duty to protect it. When the hot weather arrived last week, many people would have opened their windows and left them open when they went out. But they may have failed in their duty to keep the silver safe.
If a burglar climbs in and steals it, the insurer may take the view that the policyholder has broken the contract, leaving it under no obligation to pay the claim.
Strangers on the premises are another cause for concern. If you call in a plumber and leave him alone in the house, insurers say you may not be covered in the event of a theft. Similarly, if you hire a cleaner and fail to take up references, they could well hold that you have behaved recklessly should she turn out to be a thief.
What conduct is regarded as contributory negligence will vary from company to company - and some policy wordings are more strict than others. Mike Harvey, a claims specialist with Co-operative Insurance Services (CIS) takes the view that a window left open would probably be put down to "momentary inadvertence" rather than negligence. But in the case of the plumber or cleaner alone on the premises, "we would want to ask some serious questions about how well you knew them," he says. "If it was someone who worked in your house regularly, and you had taken up references, I think we could be persuaded that your trust in them was reasonable. But if it was a workman picked out of the phone book who you had never seen before, I think any insurer would probably take a different view." The best advice, aside from taking care in the first place, is to check your own policy wording and/or talk to your insurer in advance of any problems.
Jean Bartlett, a business executive who lives in the Midlands, found herself penalised by her insurer after she called in a builder to mend her patio door. She had seen his number advertised in a local shop window. "It was just before 5.30pm when I realised I had to collect some dry cleaning," she says. "The guy asked me to pay him before I left, because he had almost finished and had to see another customer about an estimate. "I got back 40 minutes later; the patio door was still open but the builder had gone - and when I got in I found that so had my video recorder and camera."
Ms Bartlett was paid only 50 per cent of the value of her claim because, she was told, she had failed to comply with the specific security conditions laid down in the policy. "The police couldn't prove anything against the builder, he said he couldn't find the key to lock the door, and the insurance company said that it was partly my own fault. I suppose they were right, but that still meant I had to pay over pounds 500 for the new video kit," she says.
Many home contents policies now include specific security requirements, particularly for homes in "high risk" areas. Norwich Union, for example, requires people in most areas of London, Manchester and Birmingham to fit and use key-operated bolts on ground-floor windows and those on the first floor that are regarded as accessible. "There is a condition in the policy that when you leave the premises, the windows must be locked with the keys removed and not left in view," the company says. Like most other insurers, the Norwich also specifies that doors must be fitted with five-lever mortice locks and that all doors and windows must be secured overnight, apart from those in bedrooms which are occupied.
In trying to decide whether an individual has behaved recklessly companies such as Guardian apply the "Varpt" test. Value of loss: if pounds 5,000 was stolen from a tin in the kitchen, was this an unreasonable sum to keep there? Alternatives: did they have a safe or security box in which to keep the money? Reason: why did they keep the cash in the house? Were they about to spend it or was it a nest-egg that should really have stayed in the bank? Precautions: what steps were taken to hide the money? Time: was it there overnight or for several weeks? By applying this test, insurers will decide if you were reckless or contributed to the loss, and so should not expect the full claim to be met.