Django Unchained actress Daniele Watts, who suggested she was detained by police in the US because of racial profiling after she was found in a parked car with her boyfriend, has been charged with lewd conduct.

The 28-year-old and Brian Lucas, 43, were each were charged with misdemeanour counts that carry potential six-month jail terms. Both are free pending their arraignment.

Daniele was briefly handcuffed last month after Los Angeles police said she refused to provide identification to officers investigating a report of lewd conduct in a parked car in Studio City.

Police said officers detained the pair after a complaint that two people were "involved in indecent exposure" in a silver Mercedes.

Daniele said she and Brian were just kissing.

After the incident Brian told KCBS-TV he suspected police mistook Daniele for a prostitute "because he was asking me questions like, 'Who is she? How do you know her? Are you together?'".