Who really solves the crimes?

So as many of you may know, I’m actually quite a fan of crime shows. I like law and order mainly but I’ve been known to watch CSI and all its spin offs along with anything else that fits the general topic of ‘who done it’. I should also note here that my parents watch a lot of JAG and subsequently I’ve watched a lot of it as well. My question this evening is in regards to the various impressions these shows leave me with. You see, I don’t actually know who is responsible for solving the crimes. I mean, if you watch law and order, it seems that the police and the lawyers do it. In CSI it’s the forensics people. In NYPD blue it’s the cops. On Profiler, it’s a profiler. In some of the stranger shows like medium (which I’ve never seen, and don’t plan on seeing) it seems to be a psychic who solves them or a dog on some shows. I guess its just left me with a really false sense of who is actually in charge of solving the crime. You don’t even really see some of the groups in the some of the shows leading me to think that perhaps their role is overblown in other shows ( ie. There are no lawyers in CSI and no dogs in medium (that I know of)). So my friends…what is the reality? And do all crimes really end up tied up neatly with a witty line just before commercial breaks and the final credits?