If you're ever asked to do a breath test by the police you might do well to insist that they turn off their radios before you blow into their breathalyser.

The advice comes from an ex-copper who wrote to us after we printed a story about police concerns about interference from next-generation handsets

He writes: "When at the Metropolitan Police training school, it was taught that PCs should not press the PTT (push to talk) button on the personal radio whilst waiting the requisite forty seconds for the lights to (hopefully) go red. Never.

"Oh, no - indeed. Definitely not. Especially if the subject was being 'griefy'. Honest."

He adds that the idea that that a PC might surreptitiously give a quick burst of transmit on his radio whilst his partner was administering the breath test to an uncooperative suspect, was similarly frowned upon.

Its worth noting here that, at least in Britain, the actual charging and conviction of drink driver suspects relies on a different test which is administered at police station.

Our correspondent explains the technique was used to annoy awkward customers.

"This merely gave the opportunity to cause inconvenience, spend time filling out the forms, apologise profusely and sincerely (again, honest) afterwards, give the driver back the keys to his car and advise him where he might find a cab to drive him back to it. At four in the morning.

"Oh dear. Terribly sorry, but we are not insured to give you a lift if you are not a prisoner anymore. Sir. No cash on you, then it's a long walk back, in the rain," he added.

Another reader, who worked for the St. John Ambulance, a first-aid volunteer service, recounts a time on duty when he saw a policeman using his radio to trigger a positive result on a breath test. Apparently it was all a bit of innocent fun and the guy was using the trick in a rather strange attempt to chat up a woman he fancied.

Our man in the St. John's Ambulance service says that ambulance radios can have the same effects on breathalysers.

It's not that we condone drink drivers, but if you're ever pulled up (and assuming you're not too drunk in the first place) now you know what to look out for. Lets be careful out there. ®

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