Err. What?
Are they even overalls? Could be multi-part suit, you know, like a uniform? And that utility belt? I'd be scared of your uni janitor then, as he's packing a sidearm and a couple of grenades, hanging off that utility belt.
What uni do you go to!! Damn scary one, that's for sure.
And yes, he is a cop. And this particular cop is in the Max-Tac division, which as others have said, hunt down cyberpsychos, much like this lady he's holding a shotgun to her head. It could be possible, and looks to be, that they ended up recruiting said cyberpsycho (and after some therapy), and have put her on the team. Or, the other possibility, is that she was already Max-Tac, and went over the edge. Her own team had to go after her like any other cybered up psycho in order to save one of their own.