Using a range of reasonable elasticity estimates from the new literature and a back of the envelope calculation, Klick and I argue that it would not be unreasonable to double the number of police officers in the United States. At current levels, it’s also my belief that police are much more effective than prisons at reducing crime and with far fewer of the blowback effects. Chalfin and McCrary do a more detailed cost-benefit calculation for individual cities and they also find that many cities are severely underpoliced (and some are overpoliced–the police force of Richland County, South Carolina probably does not need a tank).
It seems to me that more police are not only more efficient than prisons at reducing crime but might be more efficient than more welfare, more school spending, food stamps etc. at improving social welfare.
Dorm rooms are often small simple block rooms but are nicer places to live than slums because you don't need to fear aggression nearly as much.
So police are one of the few things that 99%+ of people agree Governments should do, and yet they spend little on it and seem to do a poor job of it!