Mr. Bravo (DayZ)

Would it be possible to make some sort of sanity loss thingy for the mass murderers? For example you'd be ok if you kill just a few people (1 to 4 or so). With more murders you'd start to go paranoid and "see/hear" things e.g. distant gunshot noices etc. Because now it's like "lol killed ya hahahahaa" and the killers life goes on unchanged. You'd think that murdering someone would have some effect on brain level. Not sure if someone suggested this kind of idea before and if someone did, nice idea!