The more fraudsters know about you, the easier it is for them to get their hands on your cash.
This week marks the start of National Identity Fraud Month, so it's appropriate that I was reminded of this truism by two scam artists who cold-called me on different days this week from the same organisation.
The first, who said his name was Paul, told me he was "working in conjunction with my local authority".
I asked him which local authority this was. Paul ignored my question and when I pushed him again, he swore and slammed the phone down. It was clear that while he had my name and home phone number, he did not know my address, from which you can make an easy guess at my local council.
When Andy phoned from the same outfit, I did not probe this point. Instead I let him talk. He told me that because I had once bought double glazing or loft insulation or cavity wall insulation, my council had put me forward in gratitude for my carbon-saving credentials for a special "Green Scheme" which would give me an unspecified discount on a new bathroom or bedroom. Hence the "working in conjunction".
"Which one do you want?" Andy asked. "Neither – I am happy with both bedroom and bathroom," was my response. The company name and website Andy gave turned out to be non-existent.
The fraud here is to get you to give as much information about you as possible which can be sold on to home improvement firms or less scrupulous organisations. As there are no set or known prices for these jobs, the discount is about as long or short as a piece of string. It's a sting.
Taking advantage of fear
Making people - especially the vulnerable - aware of the threat of identity theft is a good idea. But some firms seek to exploit this fear with their own commercial enterprises.
In November 2012, Card Protection Plan (CPP) was fined by the financial watchdog (then the FSA) for the widespread mis-selling of identity theft insurance. As Which? magazine put it some time ago: "You might be offered impressive-sounding levels of cover for losses that may arise due to fraud. A promise that you'll get £100,000 worth of protection might seem tempting – but in reality, you already have free cover under the Banking Conduct of Business rules and the Lending Code."
Under these rules, your liability is actually limited to just £50, provided you haven't acted fraudulently or with gross negligence. This is less than the average identity theft insurance policy premium, and often banks and credit card providers waive this fee.
Identity theft is rare, but it is nasty with both account holders and banks interested in preventing it. You may feel more comfortable shredding your unwanted documents at home, but, despite what shredder firms say, few identity thefts come from a trawl through rubbish bins.
In any case, receipts only show the final four figures of the sixteen figure credit or debit card number, which leaves a lot of combinations for the scammers to go through, plus guessing the three digit secutity code, which is found by the signature strip.
You are far more likely to lose important data through an activity like the phone calls I received where you are conned into giving personal details to a total stranger.
In fining Card Protection Plan £10.5 million, the regulator drew attention to the way sellers created a climate of fear by mis-quoting bank statistics on both the problem and the time taken to rectify the matter. CPP also suggested that everyday activities such as taking in a neighbour's post or parcels or using the internet ratcheted up the risk, a contention the watchdog didn't agree with.
Protecting yourself from identity theft is really a matter of common sense. Be on your guard if you receive a call or email supposedly from your bank, asking to confirm personal information - banks will never contact their customers like this. Similarly, don't publish too much information about yourself on social media.
Finally, if you live in a property with a communal postal area, take steps to protect it.
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