While all the talk at Westminster is of Lisbon, Legg and quantitative easing, on the streets of London and our other major cities much of the talk is of something else entirely. There is a new weapon in town: lethal, intimidating and yet openly carried, largely with impunity.

While an illegal gun will get you ten years inside, and a knife four years, there is a weapon that can tear off a man’s arm but will get you only up to six months or, more likely, a small fine. More and more people are using their dogs as instruments of fear and attack and they are choosing certain types and breeds. It’s not just the owners we must be concerned about; there is also something in the dogs that must be considered. These breeds are chosen for a reason.

Over the past few years, the proliferation of the “weapon dog” — American pit bulls and other bull breeds — has been prodigious. From 2002 to 2006, the Metropolitan Police picked up 43 weapon dogs. In 2008 they seized 719. This year they are on target to remove more than 1,000 animals from London’s streets. Battersea Dogs Home reports that bull breeds account for nearly 50 per cent of its “inmates”, a proportion that has doubled in the past five years. In England and Wales the number of prosecutions brought under the 1991 Dangerous Dogs Act has also more than doubled in the past 10 years, and the number of convictions has tripled. And on any given night there are hundreds of seized dogs in taxpayer-funded kennels, awaiting judgment.

Britain is not alone. In Denmark, the kennel club estimates that the number of these dogs has increased from 1,000 in 2002 to 20,000 today. So concerned are the Danes that dealing with this menace was a major issue in their party conference season. Many countries in recent years, including Germany and Canada, have recognised the rise of the fighting dog and introduced draconian legislation to stem it.

In the UK there is a consensus among people on the front line, from the RSPCA to the police and local councillors, calling for urgent action, not least because of the appalling animal welfare issues involved. Keeping an aggressive dog often involves torturing it and, of course, fighting it. The RSPCA says its hospitals are “full to the brim” with weapon dogs that have been stabbed, burnt, beaten or injured in fights.

Various attempts to replace or amend the clearly ineffective 1991 Dangerous Dogs Act have been made. This year Lord Redesdale introduced a new Bill into Parliament. Needless to say, it was not allocated enough time to proceed. Westminster, it seems, is too busy to deal with an issue that blights estates and neighbourhoods across the land.

This is a difficult and emotive subject. The dog has a special place in our psyche and the “bull-type” in particular has deep cultural resonance. So it is no surprise that one of the biggest problems the police face is persuading a magistrate that Satan, the eager doggy wagging its tail while a tearful family sobs in the gallery, is a canine thug, forcing people to cross the road and cantering round the park attacking other dogs and terrifying kids.

Indeed, the assumption most people make when trying to tackle this issue is that these dogs are innocent animals. It’s not the dogs that are aggressive, it’s the owners who make them a weapon, goes the thinking. This approach means that all attempts to amend or replace the Dangerous Dogs Act have focused on the responsibilities and punishment of owners. They have dispensed with the idea of banned breeds or types.

Clearly, owners are part of the solution: they are in possession of a weapon and should be treated as such. But while welcome and vital, this would still miss an important point: certain types of dogs are inherently more aggressive than other. At the top of the list are bull breeds, developed for one purpose: to attack and fight.

Bull terriers were bred as weapons, to duel or bait with, for their owner’s entertainment and status, and only once we recognise their atavistic instincts, as those who train them to fight do, can we start to frame legislation that may have a lasting effect. As well as punishing owners appropriately for use of this weapon, we should be bolder about removing it from circulation altogether.

In Ontario, that is what has happened. The provincial government produced a law that banned all bull breeds and derivatives, including pitbulls and the Staffordshire bull terrier. All such existing dogs had to be registered, neutered and muzzled, leading to the bull-types dying out and owners learning to love the labrador or pug. The result? A huge fall in the number of dog-related injuries and incidents. This approach manages to be both humane to those who have a dog of this type and draws a line under the problem.

Serious penalties will make dog owners think twice, but surely it is time for us to look to our Commonwealth cousins and find a way gently to phase out the canine weapons that terrorise the streets of Peckham, Toxteth and Moss Side.

Kit Malthouse is a member of the London Assembly and Deputy Mayor for Policing in London

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