Photographers who chased actress Reese Witherspoon from her gym to her home will not face criminal charges, Los Angeles authorities said on Tuesday.
Witherspoon has two children with her husband Ryan Phillippe
The Legally Blonde star told police her car was surrounded in April by snappers who tried to force her off the road.
"I have no doubt Ms Witherspoon was besieged by the paparazzi that day," said Detective Jeff Dunn, head of the LAPD's Threat Management Unit.
But prosecutors said they could not be certain a crime had taken place.
Police examined security camera footage of the incident in the gym car park and at the entrance of Witherspoon's gated community in west Los Angeles.
However, they were unable to obtain evidence of false imprisonment or any other crime.
"In this specific instance we couldn't prove any criminal behaviour by the paparazzi," said William C Hodgman, head of the district attorney's target crimes unit.
The incident is one of several recent allegations of celebrity photographers initiating confrontations in order to secure pictures.
In May, US teen star Lindsay Lohan suffered minor injuries when photographer Galo Cesar Ramirez allegedly crashed his car into hers.
It followed comments made by Leonardo DiCaprio last year in which he expressed fears that so-called "stalkerazzi" might cause a fatal accident.
Witherspoon, star of Vanity Fair and the Legally Blonde films, has two children with her husband, actor Ryan Phillippe.