She raped and murdered Leslie Mahaffy and Kristen French right along with Bernardo, ya know. It's not like she was just the passive camera operator or anything. Besides which, it was her idea to offer up her little sister to him AND she encouraged him to carry on, if not actively helped him, during his days as the Scarborough Rapist. She's just as fucked up and dangerous as he is, maybe even more so because she basically got away with it.