2003 Subaru Impreza ignition

Sounds like your shifter mechanism is damaged, this is a problem I have been seeing lately with newer products, the shift interlock is not working, and will require a trip to the dealer, or a really good shop. The shifter will need to be disassembled, and there is a chance of deploying the airbag if not done correctly and the shifter is on the column, so please have it checked out by a professional. You can be seriously hurt in an airbag deployment.