Police Investigation Turned Over To DA

The investigation into Trevor Bauer's alleged assault is over -- police have turned over their findings to the L.A. County DA, who will now decide whether the MLB All-Star will be charged with a crime.

TMZ Sports has confirmed ... the Pasadena Police Department has concluded their months long investigation into 30-year-old Bauer -- who has been accused of hitting and choking a female companion without permission while they were having sex.

Now, detectives have sent all relevant info to the county District Attorney.

Bauer had a huge win in court last week ... after a judge dismissed the accuser's request for a permanent restraining order, determining the pitcher's actions did not exceed the…