Britney Spears has called on California police to help her battle the paparazzi who follow her everywhere, but law officials have told her there's nothing they can do.

The pop superstar reveals she flagged down officers during one recent hair-raising paparazzi chase and alerted them to the maniacs following her.

She tells America's People magazine, "I've pulled over and asked the cops, 'Could you please help me? They've been driving recklessly back there.'

"They say, 'Sorry, ma'am, I can't help you. This is how it is.'

"I mean, Princess Diana got killed by one of these people. They're crossing the line."

Spears was recently criticised when she was spotted driving with her baby son Sean Preston on her lap - in an effort to avoid the paparazzi."