Authorities said a sheriff's vehicle was preparing to turn right onto Santa Monica Boulevard from Robertson Boulevard when a black BMW, driven by Bynes, hit the right rear panel of the deputy's vehicle while attempting to pass at about 3 a.m.
After further investigation, the deputy determined that Bynes was under the influence of alcohol. The 26-year-old was booked at the West Hollywood Sheriff's Station and released on bail.
No one was injured in the incident. Both vehicles had minor paint damage.
Bynes has starred in movies like "She's The Man" and "Hairspray." In 2007, Forbes listed her as the fifth highest paid celebrity under 21, with earnings of $2.5 million.