The Hollywood star Scarlett Johansson was heading for Disneyland to enjoy a day off with friends when a swarm of photographers began chasing her Mercedes. A tense game of cat-and-mouse ensued, lasting 45 minutes and only ending when Johansson’s car crashed into another that was carrying a family.

Nobody was hurt, but the actress was so shaken by relentless hounding from the paparazzi that she fled her home in Los Angeles for a while last year. From today, however, such aggressive tactics will be banned when a law comes into effect in California, designed to curb a new breed of baying photographers.

Dubbed the “stalkerazzi”, they stop at nothing to get the right shot. Lying in wait for a snatched shot is not enough. Instead, some engineer the action by goading, confronting or pursuing their prey. Many reckon the damage caused by ramming a lens into someone’s face or crashing their car will be worth it, because the returns on their shots are so lucrative. With worldwide syndication, pictures can be worth hundreds of thousands of dollars.

But the new bill, signed into law by California Governor and actor Arnold Schwarzenegger, will hit the photographers in the pocket. They will be forced to pay three times the damage they cause and will be unable to profit from any shots taken. Cindy Montanez, the US legislator who drafted the bill, said: “Now the paparazzi are going to have to think twice about chasing a celebrity anywhere in California.”