Meta: Karen and Petty Crooks
I've been saying, "Someday I'm gonna write the meta about Karen and petty crime," for, like, a year now. The time has come. (Trans.: I'm bored as shit at work and have been on hold for fifteen straight minutes and have been thinking about this a lot lately.)
I absolutely believe that Karen has a background in petty crime. I doubt she robbed banks, but I wouldn't be surprised if she dabbled in other shit, and I'm Very Curious as to what the hell her driver's ed looked like. Who taught that woman to drive, because she's a fucking master of not swerving/spinning out when other humans would do so. (Seriously, most people would swerve dangerously and probably wreck if somebody started taking pot shots at their wing mirrors, and tbqh, getting T-boned by a larger vehicle should, by all rights, have sent Karen into a spin and thus totally off that tiny-ass road.)
I really get the sense that even if Karen has never burgled houses before (and I doubt that), she'd probably be a decent burglar. She's got a good sense of where to hide small, valuable objects (check out that vent trick in 1x01 -- she put that flash drive in a nicely out-of-the-way room, where you wouldn't expect people to store electronics, in a vent that was above eye-level and would have therefore skated past most people), she's got at least a mild sense of how to make herself unobtrusive in a room (look at her sitting in the back of that auction back in S1, sketching -- no eyes are on her except Ben's), and we know she can pick locks. In fact, that lock picking is really interesting to me -- not only did Karen card that door open on the first try, she was able to identify a door that potentially COULD be carded open on the home of Frank "It's not paranoia if you were involved in black ops and had a habit of seriously pissing off your CO's, one of whom was smuggling in heroin somehow" Castle.
Furthermore, look at how she deals with Grotto and Turk. Grotto is an obvious criminal who's running from the Mob, and yet she's totally comfortable with him right up until he starts bleeding on her. Same for Turk. This woman is used to dealing with some pretty rough customers, holding her own, and persuading them to follow her instructions. Not the actions or reactions of somebody unused to being around sketchy people.
Take a look at the way she handles Grotto in the hospital, even. And I'm not just talking about the aliases -- Steve and Isabel Schaffer -- or the story, but Karen walked into that room and made a plan to get the fuck out if she had to. She knew where the emergency exit in the opposite direction of Frank was (and hospitals are frequently maze-like; I WORK in a hospital and would be more likely to hide than run from an active shooter, just because I don't know where my exits are yet), she had identified that emergency stairwell well enough that she was parked near it. Parked right next to it.
Karen's a survivor, sure. We knew that from the way she gouged Officer McStrangle's eye and how she got Wesley's gun away from him -- what was clearly a desperate move, possibly something learned in a women's self-defense course -- but the hospital is beyond being a good survivor. This is situational awareness and tactical thinking that you just plain don't really get out of civilians.
You do get this kind of thinking -- on-the-fly lies, exit routes, egress points, quick getaway vehicles -- from smart, experienced criminals. (Also spies. Seriously, one of these days, I need to write a heist fic.)