Its the same woman (assuming that really is a woman's brain inside that body). That's the point. They take people that have gone berserk, reform them, and use them as cops.
People are robots? And way to understand that plot point. Just thought the same people who made sex trading cards like putting lipstick on ladies. I thought it was a sex bot that was modified to kill. No person just happens to have evil giant blades. Why would the cops "reform" an evil robot? Just destroy it and build a new one...