When Norah Kennedy travelled with a canister of Mace for protection, she never dreamed she would end up in a police cell.
Traveller, beware! Have you got CS gas in your handbag? No? Are you absolutely sure? Not even a discreet can of Mace, a self-defence spray frequently carried by women, which is readily available and completely legal in the US, France and many other countries?

Norah Kennedy, a 48-year old self-employed basket-maker from Gloucestershire, certainly didn't know she was carrying CS gas when she and her husband Erick set off for a holiday in Dublin last September. But after going through security in Heathrow's Terminal One, she soon discovered otherwise. "I had just gone through the metal detector when a security guard found the Mace at the bottom of my bag", says Norah. "They led me to a side room and called the police, who arrived 10 minutes later and took me to Heathrow police station. On the way there they said it was CS gas, and that carrying it was just like carrying a loaded gun.

"Then they asked why I was carrying it, and I said, `I've suffered one serious attack abroad and several other incidents and it's there in case I needed to defend myself.' In fact I had had it in my bag since my mother sent it from America five years ago. I must have taken it on at least a dozen international flights, and although my bag was checked every time no one ever said a thing." Norah felt that the police were sympathetic. But after detaining her for 40 minutes the duty sergeant told her that she would be charged. Then he had her finger-printed, photographed and locked in a cell for 45 minutes, before formally charging her under Section 4 of the Aviation Act.

"By this time I had missed my flight and was getting a bit upset," she says. "How was I meant to relate this old spray can to CS gas?" But she was lucky - the police released her on bail and the airline found room for her and Erick on a later flight.

Back in Gloucestershire two weeks later, Norah's solicitor tried to persuade the CPS to drop the case. Instead, they added a new charge under Section 5(1) of the Firearms Act, which makes it illegal to carry CS gas anywhere in Britain. Norah was duly prosecuted before Uxbridge magistrates, pleaded guilty and was convicted.

The penalty was modest enough - a pounds 25 fine with pounds 30 costs. But she had suffered a lot of anxiety, and finally emerged with a criminal record. The overburdened criminal justice system had meanwhile spent at least pounds 1,000 on bringing her to court.

Heathrow police and the CPS both insist that they deal with each case on its merits. But the police concede that there is "a strong probability" that they would charge in such cases. And one local solicitor says that Heathrow police charge anyone caught with an offensive weapon at the airport, even if they are of previous good character and would be let off with a caution anywhere else in the country.

According to the Clerk of Uxbridge Magistrates Court, Martin Hamilton, cases involving offensive or prohibited weapons at Heathrow come up every day on average, and normally attract a fine "at the very least". "Mace is quite serious in terms of what could happen if it was released in the confines of an aeroplane," he says. "Other weapons, such as knives, are also dealt with very seriously." He adds that it is not unusual for people to be held overnight, and to miss their flights.

All the more reason, argues Norah, to warn travellers of the risks they may be running. "Hundreds of people must be carrying Mace into Britain every day without knowing they're breaking the law. Why aren't there warning signs in airports, and bins to dump the stuff in? Surely this would be more effective than prosecuting people who didn't even know they were doing anything wrong?" No, says the Department of Transport. "There are so many forbidden items that if you were to list them all on a sign it would defeat its own purpose as no one would read their way through it," said a spokesman. "Our view is that it would not be practical to list everything you can't take on to an aircraft."

Traveller, bewaren

What's the best way to...

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