Have celebrities finally snapped?

Amy Winehouse's injunction against the paparazzi reveals a growing frustration with picture agencies and their methods

You may have noticed that, while just a few months ago you couldn't open a tabloid newspaper or celebrity magazine without seeing a photo of Amy Winehouse - usually taken late at night with the singer in a dishevelled state - there haven't been many pictures of her recently.

The Guardian revealed over the weekend that Winehouse had successfully, and relatively quietly, obtained an injunction preventing picture agencies, and the photographers who work for them, from following her and gathering outside her house. A sign outside her new home since 30 March has warned photographers not to come within 100 metres. The pop star Lily Allen won a similar injunction earlier in the same month preventing two picture agencies - Big Pictures and Matrix Photos - from harassing her, approaching her within 100 metres of her home, or taking photographs when she is in the homes of her family or friends.

Both follow an action brought by the actor Sienna Miller, who sued Big Pictures, one of the biggest agencies for celebrity photographs, for harassment and invasion of privacy, and was awarded £53,000 in damages and costs as part of a settlement that resulted in the agency's photographers being forbidden from following her. Alan Williams, the chief executive of Big Pictures, declined to comment on the injunctions, except to say: "We believe in the right of a photographer to take pictures in a public place."

Celebrities have increasingly turned to injunctions against the paparazzi, claiming an inability to live ordinary lives. How did the once-umbilical relationship deteriorate so much? After the death of Princess Diana, there seemed to be a collective surrender by paparazzi photographers. But with the internet and the success of celebrity magazines creating demand, as well as the growth in the number of amateurs, there are now more paparazzi than ever. In Los Angeles, they are known as "gangbangers", says Nick Stern, a British photographer who divides his time between London and LA. Last year, Stern resigned from Splash picture agency, when he felt the hounding of Britney Spears had gone too far. When Spears was taken to hospital in February last year, the ambulance needed at least 12 police motorcycles to escort it through a swarm of photographers.

The picture of Spears having her head shaved is rumoured to have fetched around £250,000. "Some days there would be 30 or 40 people trying to take her picture. There is very little skill, technical or journalistic, involved - it's just a crazy fight, pure aggression and persistence," Stern says.

The publicist Max Clifford remembers one instance last year when he was in a car "with someone who had done something they shouldn't with someone", and a photographer chasing them on a motorbike came off the road and nearly hit a woman with a pushchair. "He didn't have any regard for his safety or those around him. That's what you're up against now. It is more fierce, confrontational and competitive. The atmosphere has changed."

Clifford blames "over-enthusiastic amateurs ... ruining it for the rest". Before, there was usually an informal agreement between professional paparazzi and the star - the star would pose for a picture, and in return the pack would largely then leave them alone. Now, anybody can pick up a decent digital camera and a laptop with mobile broadband for a couple of thousand pounds and become a paparazzo. Even photographs snapped on mobile phones can reach dizzying sums - the Mirror is thought to have paid about £100,000 for the grainy phone footage of Kate Moss appearing to snort cocaine.

"I know it can be presented as celebrities not wanting photographs to be taken, but this is more about the extraordinary lengths that [photographers] will go to get pictures," says David Sherborne, the barrister who represented Allen, Miller and Winehouse. "It makes doing everyday things that you or I take for granted miserable and dangerous." Sherborne says he thinks more celebrities will seek injunctions, "when they realise something can be done about it".

In a newspaper interview a few weeks ago, Allen described an incident when she left her house and photographers in seven cars followed her. "I turned into a T-junction and they all ran a red light, then tried to overtake on the inside. A woman had to slam the brakes on her car as they cut in. I braked too, of course, and this guy ran into the back of me. I got out of the car. I was shaken up ... Instead of talking to me, like a decent human being would, he got his camera out and started taking pictures, and I just thought, 'I've had it with the press, I can't do this any more.' I got back into the car and called my lawyer."

Dan Bozinovski is one of the photographers affected by Allen's injunction, though he denies that he has ever behaved in an unacceptable way. How does he feel about celebrities taking out injunctions? "I think there should be some way of regulating photographers, rather than taking out injunctions against whole agencies.

"A certain class of people is going to become untouchable. The more money you have for lawyers, the more privilege you can buy." Celebrities can't have it both ways, he says. "A lot of publicity [for Allen] has been generated through us. When she had an album out, her PR was working overtime to tip us off about where she would be. That's the game."

That said, Bozinovski does admit the pack has become "much worse. Most photographers are freelancers who joined the industry in the last couple of years. There are so many more photographers now, so people aren't making as much money and they're getting desperate for that great shot." He says that he has been sworn and spat at, and colleagues have been beaten up by bouncers and celebrities' security guards. "I don't know if I'll be doing it by the end of the year," he says. "It's getting harder, for less money and you have to risk more and more."