Art of darkness: Dave Brown’s merciless satire

I'm a visual journalist. I provide a personal view of a news story, just like the other writers on The Independent's comment pages. But, whereas an 800-word article is easy to put to one side and think, "Maybe I'll read that later," the thing about a cartoon is that you can read it in seconds. That's the cartoonist's strength – I can make a point very rapidly. Hopefully, of course, you can go back and get a bit more from the cartoon later as well (perhaps once you've finished reading the rest of the day's paper).

Beyond what used to be called the broadsheets, there's very little market for political cartooning nowadays. The tabloids either don't employ a cartoonist, or they'd rather have them do cartoons of Posh and Becks than something political.

Click here for months of Dave Brown's most recent cartoons

Most cartoonists have developed a recognisable style that somehow accommodates their paper. They just seem to fit together. Steve Bell seems to fit with The Guardian, and Peter Brookes with The Times. If you swapped them over, it would look slightly odd. I don't think that what I do would fit in the Telegraph, for instance.

For one thing, I don't suppose the Telegraph would like my politics, but also I don't think they'd be happy with my style. I think it would be too aggressive, too hard-hitting for them. Generally, the people I most enjoy drawing are the ones I dislike the most. You can just put so much more bile and invective into the caricature. Occasionally I get to draw somebody I respect or broadly agree with, but there haven't been that many of them. I'm a long way to the left of New Labour, so it's been just as easy to attack one bunch of Tories as it was the last bunch.

I met Gordon Brown briefly once, and he said: "You draw me far too fat. I'm not that fat." But then I heard exactly the same story from Martin Rowson, who'd met him once as well, so it's obviously his stock line of conversation with cartoonists. Maybe he's hurt by the fact that we draw him as a rather huge, hulking man, but I can't imagine he's really that bothered. On the other hand, John Major was very thin-skinned and touchy about the way he was depicted. But, of course, if a politician complains to a cartoonist, you know you've hit a nerve, so you just carry on doing it.

John Reid once complained that I'd started drawing him with a cigarette in his mouth. During the debates over the smoking ban, he'd commented that it was one of the last refuges for working-class people. So I just started to draw him with a cigarette in his mouth, and he moaned: "I gave up years ago!" It was something I had planned to do just once or twice while the comment was fresh in people's minds. But instead I carried on, and every time I came back to John Reid he became a Glasgow hardman with a fag clamped to his bottom lip.

I've even had a few politicians buy my cartoons over the years, but not many. There are some who boast that they're not bothered by it, that they have a thick skin and like to have the cartoons. Michael Howard was one of them. I don't know whose cartoons he was talking about, but he's never bought any of mine, and to my knowledge he hasn't bought any from the other major cartoonists that I'm friendly with. So what are these cartoons he claims to be going out and buying? They're obviously not the really powerful ones.

There used to be a tradition of old-fashioned Tory grandees getting the original cartoons from the cartoonist in exchange for a crate of wine. The attitude then was that they were all part of the same Westminster club.

I don't think that happens any more. Cartooning is much more hard-hitting today. For a while, it did get a bit too gentlemanly and civilised, but now we are getting back to the scabrous, rumbustious, 18th-century tradition of James Gillray, where cartooning started. The form became a little bit polite for the whole of the 19th century, and it took half of the 20th century to shake that off. We're back now to a much more irreverent and robust sort of satire.

Gillray is the starting point for political cartooning, but there's another English strand of humour that I like to tap into and redirect in a political direction – fun, silly stuff like Donald McGill's seaside postcards and the Carry On films. As for other cartoonists, I tended to read and admire Les Gibbard when he was drawing in The Guardian. He was very good at telling a story visually. And I'm always dazzled by the range and freedom of Ralph Steadman's work. I come from a fine art background, so those things are always in my head. But then Goya was influenced by Gillray as well; his etchings treat the barbarity of war with very powerful, simple, black-and-white images that immediately make a connection with cartoons.

Picking characteristics for a new subject is just a matter of looking. The raw material is already there. It's the art of the bleeding obvious. You have to get a lot of pictures of the subject, and often there are things that don't come out in still pictures, so you pick those up from the telly. Gordon Brown's big characteristic is the thrusting bottom lip and the jaw drop at the end of every sentence. I tend to make his bottom lip much heavier than it is, and the mouth is just a big black hole without any teeth. Once you capture that big characteristic, you start to get to the nub of what a person is like.

It's amazing how characters change. A lot of people seem bland when you start drawing them when they're fresh on the scene, and it takes a while for them to start living up to their caricatures. Most people's take on George W Bush when he first arrived was that he was a pale imitation of his father, and the early caricatures all look like a pocket version of George Bush Snr. But of course Dubya's been great to draw: he has that simian walk, with his hands by his side, and that great pouting mouth when he pushes his lips out. He has a fantastic chimp-like way about him. Then again, you get to a point where a person's been drawn to death and you're begging for someone else to come on the scene.

I've never thought, "I shouldn't have done that" after the fact. Somebody asked me the other day what the difference is between caricature and insult. The difference is the motive. You don't draw Nicolas Sarkozy as short just to laugh at the short man. It's to make a point about his political or philosophical inadequacy. You're saying he's a man of small stature not in inches, but in intellect. An insult is just based on a person's physical look. In a cartoon, you make that visual aspect a metaphor for what you think of them.

How long does a cartoon take? How long is a piece of string? You could have an idea within half an hour and have the rest of the day to draw it. Then, if you want to paint an elaborate watercolour background, you have plenty of time. Alternatively, you can spend five hours banging your head against the drawing board with nothing coming, and end up with an hour or so to draw it. Sometimes I have an idea and start work, then halfway through the day a better idea strikes me, so I rip it up and start again.

I manage to absorb the day's news by osmosis. The Today programme comes on at 6am and I lie half-asleep trying to ignore it, then I sit down with all the newspapers over breakfast. I have BBC News 24 on, too, which means that there are about three sources of news competing for my attention.

At about 10.30am I call the comment desk. By that time, I'll have a shortlist of the main stories. I'll have a discussion with Adrian Hamilton, the comment editor, and between us we either alight on one story or choose two or three that are good, from which I decide the one I like best. Having decided on a topic, I just sit down and try to decide what I think about it, and how I'm going to approach it.

Once I've got an idea I'm happy with, I do a rough pencil-sketch and fax it over to the desk for them to approve. It can be nice to have another person's point of view, but you do also have to trust yourself. If you have a cartoon passed round the office, then eight different people will give you eight completely different views on it. You'll end up with a cartoon drawn by committee, which will please nobody. In the end, you have to trust that what you find funny and what works for you will work for the rest of the audience. You get a feel for it over the years.

I've always drawn cartoons. When I was at school, I made up my own comic strips. I sat at the back when I was bored in lessons, looking as if I was working. I wasn't making notes, I was caricaturing the teacher, but that was safer than staring out of the window.

I went to art college wanting to be a painter, taught for a while, and then packed it in to try to paint full-time. But it was too expensive – my studio was bulldozed to build a Tesco, and I couldn't afford anywhere else in London. I was living in a bedsit, painting enormous great panels that wouldn't fit in the room. I thought, "I have to find a smaller art form." I had always drawn cartoons and been politically motivated. As a teacher I'd done cartoons for the local union magazine. Then I won a competition that The Sunday Times ran, and they gave me my first job on the back of it. I thought I should start taking cartooning a bit more seriously after that.

I heard a quote the other day saying that cartooning was "the continuance of war by other means". That's not quite right – it's not really war, it's more like ersatz assassination. We're lone snipers in the book depository. Unfortunately, when you have a sharpened pen rather than a rifle, you have to hit them several times to have any sort of effect.

Our new book and exhibition, An Independent Line, features the work of all three of the paper's cartoonists. We have pocket cartoonist Tim Sanders on the grassy knoll, and Peter Schrank, the Independent on Sunday's elusive third gunman, to back us up.

Click here for a gallery of Tim Sanders's cartoons

Cartooning is a way of taking back a little power from the bullies who run our lives. A cartoonist is a lone assassin who keeps on firing away at them and hopefully, if he manages to get enough direct hits, he might find a little weak spot and help to bring them down.

The exhibition An Independent Line is at the Political Cartoon Gallery, 32 Store Street, London, WC1 until 18 October. The book An Independent Line is available to readers at a reduced price of £17.99 inc p&p (RRP £19.99). To order a copy, call 020-7580 1114, quoting 'Independent'. (www.politicalcartoon.co.uk)