In an honest/meta sense I imagine it’s because NPCs arn’t quite up to complex behaviors yet.
Thus being why they neither attempt to process/apprehend you, nor lay the beatdown to some zombies.
Ideally I imagine they would detain you, strip you of equipment and shove you into a cell full of other ‘criminals’… possibly with the option to try and pay bail to avoid spending the night with a room full of zombie mutants.
Really, I’d figured these copbots would have trouble recognizing black people if they really couldn’t tell a zombie is/was human (there was actually a case or two where face recognizing cameras have had this exact problem, or believed asians were always blinking during a photo. While I could believe in a grim future police programed ‘rasis-bot’ I somehow think ignoring them entirely would NOT be the desired behavior.)