There are two problems trying to interview aggressive men with aggressive dogs, one practical, the other ethical. The practical problem is that genuinely aggressive men with genuinely aggressive dogs don’t want to be interviewed, still less photographed. These Bill Sikes characters tend to disappear, swearing, with Bull’s Eye around a corner as you approach. Appearances can in any case be deceptive. You find some likely-looking candidate togged up in Lonsdale and adidas, teeth missing, shaved head, 80lb of canine energy straining at the leash, and he turns out to be a sweet guy with a sweet dog.

One such was Lee Randall, 36, an asbestos remover by trade, whom I met in Bow in East London, his American boxer Che at his feet. “Some people are scared of her, but it’s not the dog, it’s the owner. It’s like a baby, or a computer. You get out what you put in. It’s the same as anything. A dog is only aggressive if it’s taught to be.” Che is fine around people, says Randall, although squirrels are another matter.

Randall wouldn’t want to be seen walking around with a toy poodle, but that doesn’t mean he has a boxer to be aggressive, or macho, or as a status symbol. It means he has a boxer because he likes the way boxers look and behave. It’s a similar story with Staffordshire bull terriers, the most popular dog in London, according to the Kennel Club. A lot of people think they’re ugly, but beauty is in the eye of the beholder. A lot of people think Staffs must be nasty too, because of the way they look, but they’re actually renowned for their good temperament, especially around children.

There is a great deal of media attention on the rise in the number of dangerous dogs, or more accurately, dogs behaving dangerously. In London last year, 127 children required hospital treatment following a dog attack, as against 58 four years earlier. In the year to April this year, the Metropolitan police seized 480 dogs under the Dangerous Dogs Act of 1991 (which outlaws the pit bull terrier, Japanese Tosa, Dogo Argentino and Fila Brasileiro. An enduring problem with the legislation is that a pit bull terrier is not a breed of dog, and therefore hard to define). Between 2003 and 2006, the number seized averaged under 40 a year. The RSPCA has also recorded a big increase in the number of calls it receives relating to dog fighting.

Despite these increases, the vast majority of men and their dogs are not remotely dangerous. There are roughly 6.8 million dogs in the UK. About 20 per cent of households keep a dog. In London that figure drops to 7 per cent of households, which still makes for several hundred thousands of dogs in the capital (an estimate – no one keeps comprehensive figures). Here lies the ethical problem: to focus on the few hundred potentially dangerous dogs with dangerous owners while ignoring everybody else is both unfair and inaccurate.

Men keep dogs for all sorts of reasons, the primary one being a deep, primitive love for the animal. Certainly, especially in London, fashion is among those reasons, but just as very few women actually want a tiny yapper they can fit in their handbag, not that many men want something large and scary. What sort of dog men have, and why, is mediated by their class, age, personality and location. And also by their self-image. And their self-confidence. And their budget. And their degree of commitment to having a dog.

Or dogs, plural, in the case of Daniel Joyce, 26, in Hackney. Since we met, Joyce has had to give Terror, his Dogue de Bordeaux/Rhodesian ridgeback cross, to a neighbour. “She was too lively.” But he still has Remy (“I used to drink a lot of brandy”) and Mitzy. They are Staffordshire bull terriers/collie crosses, six stone a piece, £30 a week each to feed. “People get jumpy around them, but they’re as dopey as anything,” says Joyce. He walks his dogs four times a day, the first time after they jump on his bed at 5.30am. “It’s a full-time job.”

He wouldn’t think of muzzling them. “There’s a couple of rottweilers in the park, proper snappy. They couldn’t defend themselves if they were muzzled.” (Untrained or uncontrolled dogs, besides the straightforwardly bellicose, are a much bigger danger to other dogs than they are to humans.) Along with his son and his mum, Joyce’s dogs are his family. While we’re talking, a woman comes up. “They’re beautiful,” she says. “They’re a credit to you.” They are, too.

Daniel Joyce is unemployed and has the time to manage large dogs. Self-employed estate agent Ray Smith, 32, needed something lower maintenance, hence Abe, a dachshund with some celebrity status in the bars of Hoxton. “Daxies basically sleep all day,” says Smith. “They don’t moult, they don’t need a lot of exercise, and he’s a ridiculously affectionate dog. Customers love him, he’s sold a fair few flats. I get stopped every day by people wanting to talk about dachshunds.”

This theme of dogs bringing people together, as opposed to tearing them apart, is echoed by many. “Dog people are united in their love of dogs,” says Rodman Primack, 32, chairman of the London branch of Phillips de Pury, the auction house. “I get stopped four times a week to talk about Theo, and that’s just the Japanese tourists. I love it.” Theo is Primack’s labradoodle, a cross-breed rocketing in popularity,already the ninth favourite in the UK. (The one, two, three goes labrador, border collie, Jack Russell.)

“I was obsessed with the idea of getting a chocolate brown labradoodle,” says Primack. “There was a bit of politics involved in getting to the head of the queue with the dealer.” Theo accompanies Primack to work: “She’s good for my stress levels.” “She’s one of the most productive members of the office,” says one of Primack’s staff.

If choice of breed is related to class (roughly speaking, dogs get stockier and their hair gets shorter as you descend the income scale), a love of dogs cuts across the usual boundaries. “You get to know other dog people and you end up chatting together all the time, about dogs,” says Gary Mason, 47, a journalist in Stoke Newington. “Sooner or later someone will say, ‘You get too many bloody Staffs or whatever in London,’ but 95 per cent of them are fine. You get the odd nutcase, whom you learn to avoid. Just like people, really.”

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