Unless you have an aftermarket alarm system which is very sensitive to motion.. A thief could bust into anything.. Soft=cut open, Hard= pry up, Topper cap=pry/break open a window, Locking tailgate=pop out the lock, standard tailgate=Open it. If you have a slider window they can just stick something in and pop open the latch or knock it out. Same as any vehicle.. If a thief knows what they are doing.. No vehicle is truly safe. Only advantage with my truck is that they will go deaf trying to steal anything with my truck horn and aftermarket alarm horn going off. Gotta love alarm systems.