Well, probably not criminals.
But I'm sure the regular law-abiding citizens wouldn't have a problem with him keeping an eye on them and keeping things safe for everyone.
You know... if he were real.
But you can almost have the next best thing by plastering a wall in one of your rooms with an image of the Dark Knight keeping vigil 24/7.
A company called Room Mates is selling quite a few wall murals with comic-related themes for uber-geeks to choose from.
You could have Superman flying over Metropolis. Spider-man webswinging.
Maybe you can't decide on any particular hero and would want to decorate your wall with a myriad of classic comic book covers. Well now you can do that too.
Or maybe, just maybe you want to go all out and proclaim your geektitude to the world (or whoever happens to visit your home).
You could decorate the walls with the bridge of the U.S.S. Enterprise:
But don't stop there.
You'll want an official replica of Capt. Kirk's chair to go with it.
And while you're at it, pick up a wall mural of the Carina Nebula to really set the mood and make the "experience" complete.
If all that is a little too much for your wallet, you could just change a few switchplates in your house for a more "subtle" nerd effect.
Happy decorating!