Her Alibi (1989)

Mystery novelist Phil Blackwood (Tom Selleck) has written countless best sellers, but he's having trouble finding inspiration for his latest book, so he goes to the courthouse to observe real criminals in action. There he encounters Nina (Paulina Porizkova), a gorgeous immigrant charged with a gruesome murder. Convinced she's not guilty, Phil furnishes Nina with an alibi and a place to stay. But, as the two begin to fall in love, Phil finds he has grave doubts about her innocence.