'Django' Actress & BF -- Charged With Lewd Conduct -- For Car Sex

10:30 A.M. PT -- Danielle and her BF just issued a statement, saying ... "We are, quite frankly, appalled and disturbed that the LA prosecutors office has chosen to file these charges against us. The LAPD has previously issued a statement saying that there was no crime committed. If a passionate public embrace while displaying no nudity is grounds for having charges filed against you, then we'd expect that everyone who engages in an extended public display of affection with their loved one will be targeted as well. Sergeant [Jim] Parker is still under investigation for his conduct and filing misdemeanor charges against us does not change his behavior.”

"Django Unchained" actress Daniele Watts may be convincing in the movies, but not in real life because she's just been charged with lewd conduct for allegedly having sex in her car outside CBS Studios.

Watts went on a campaign against the LAPD ... accusing cops of racism for cuffing her after people complained they were banging in the Mercedes in Studio City. Watts, who claims she and her BF were just making out, walked away from cops in a fury, so they cuffed her and brought her back.

Prosecutors listened to the LAPD audio -- obtained by TMZ -- and realized what was up. Armed with various witnesses and photos of Watts straddling her BF with her breasts exposed, she and the BF were each charged with lewd conduct in public.

The crime is punishable by a maximum of 6 months in L.A. County Jail.