Lindsay Lohan is a most wanted woman ... because TMZ has learned a SECOND police department wants a chitchat with the actress to determine if she committed a crime by lying to cops.

Law enforcement sources tell us ... Santa Monica police detectives have been trying to get in touch with Lindsay to ask her questions about a car crash last June, when she slammed into a big rig on Pacific Coast Highway.  Sources say Linsday's lawyer, Shawn Holley, called the station and complained that cops should not be calling Lindsay directly because she has an attorney.

We broke the story ... Lindsay lied to cops when she told them she was NOT the driver, but a passenger.  Cops are convinced Lindsay was indeed behind the wheel and are now investigating 

Sources tell us the follow-up questions relate to Lindsay's alleged lying to cops -- which is a crime punishable by 1 year in jail.  We're told the case will be referred to prosecutors.  It will also be sent to the L.A. City Attorney for a possible probation violation in her necklace conviction.

And, as we first reported yesterday, the LAPD is investigating Lindsay on another front.  She's now a suspect in a $100,000 theft of watches and sunglasses at at Hollywood Hills home, and cops want to speak with her STAT.   LIndsay's lawyer shut detectives down, saying no way would she cooperate.