I like science fiction as much as you do. I watch Law & Order in its various iterations. I watch CSI, CSI: Miami, CSI: New York, and I'd probably watch CSI: Boise. But if you have ever spent time observing policing up close, you have to suspend disbelief when you watch television. It's not hard if you grew up watching Perry Mason.
Effective law enforcement, in the main, is not about solving crimes. It's about catching criminals. It's not the same thing. With the state having budget problems, the Department of Corrections has suggested releasing 4,000 non-violent felons to save money. Before we take that step we need to recognize how police work happens in the real world.
(We aren't talking about high-profile murders, of course. The manpower, the lab testing, and the court resources are there in these cases. The police investigation, the coverage, and the trial of the murdering scum in the Christian/Newsom case is an exception to the usual.)
To have a low crime rate and have a safe community it is necessary for law enforcement to know who the criminals are. No, police and sheriff's deputies don't go out to every crime scene and "dust for prints." I don't know if they even have any of the magic sprays they use on CSI to make fingerprints and blood visible. If you've ever been robbed, you may have been shocked to learn that the most traumatic thing that has ever happened to you results in a routine police report and no investigation. They don't assign two detectives and three crime-scene techs to try and recover your lawn tractor and weed eater. Each episode of CSI spends the yearly budget for Knox County's detective division.
You often see statistics that reveal a high percentage of prisoners are in for "mere" drug use or drug possession. Some people conclude that if we decriminalize drugs, we could free up space in prisons for "real" criminals. In the real world those "mere drug users" finance their drug habit by burglarizing your house, stealing cars, and eventually knocking off stores and banks. It is not unusual for a career criminal suspected in two dozen burglaries to take a fall for use or possession of drugs. When they get sent off to prison, the number of burglaries goes down dramatically.
Often, thefts and burglaries are the work of a gang of related criminals who use the money to live without working and spend their time enjoying stimulants. It is hard to catch them in the act of burglarizing a house or stealing a car—you can't follow them 24/7. So officers work on catching them doing something they can prove. Sometimes it's possession of stolen stuff before they get rid of it. Usually it's for drugs.
So that big bag of marijuana or OxyContin pills they bought with their ill-gotten gains gets them off the street. You get enough of them sent off to prison, the amount of theft and burglary goes down. Call it street justice. But it's why three-strike laws are so effective in policing. If someone has been arrested and convicted three times, you can assume A) they are really stupid, or B) they have committed numerous crimes and gotten away with it. You send them away for a very long time.
Rural counties and small-town cops have, since time immemorial, rounded up the usual suspects when they have a crime wave. Somebody rats somebody out and they go to the pen. Crime goes down.
New York is one of my favorite cities. It got to be a crime-ridden hell hole. Mayor Rudy Giuliani and his police department went after graffiti artists and subway turnstile jumpers, and began executing unserved arrest warrants. Career criminals were thus caught in a net, sent up, and the city became livable again. But the program worked because police concentrated on catching criminals and putting them in jail, regardless of the severity of the charge.
Think about this before you allow state government to release 4,000 non-violent felons back into the population.