Specialization is a thing within policing as much as it is within the rest of life. It's not like the same person who knows how to investigate a murder scene is equally capable of investigating complicated financial crimes on Wall St.
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In terms of aligning incentives, there are various situations where there would otherwise there would be a mismatch of "who pays for this/who's responsibility this is" vs "who this is meant to serve".
On your examples:
Campus PD - College has equal/larger population than town. Town-college relations are often tense at best. Voters in town have no interest in spending their tax money on adequate policing for the college, college has no interest in donating a bunch of money to the PD to maybe get better services that they still have no say in. Students often heavily distrust the local PD and are unlikely to report crimes to them. It's still a problematic structure, but the premise that it would be better without is questionable.
Transit Cops - No individual town or city is going to patrol the system coherently otherwise, and areas which utilize the service less are unlikely to spend significant resources policing it. Services which cross state lines also have jurisdictional issues even with just using normal state-level police.
I don't see why every government department needs a police. Yes there are specific crimes that you might want to investigate, but you don't have to have police for that. Look for example to IRS they can have investigators, but they don't need police powers. If they need those they can go to the police.
It's not only that every government department has a police now, it's also that (nearly) every one of them has swat teams, I mean for heavens sake the department of forestry has a swat team!
There are also a lot of other public officers with limited police powers and different reporting, just like in the US - officers of the courts, public health inspectors, the Ordnungsamt (public order office), forest rangers, officers of the bureau of standards etc.
Until a few decades ago, it was even more splintered, and the border police and railway police were only integrated into the federal police in the 1990s if I am not mistaken...
[1] https://nl.wikipedia.org/wiki/Dienst_Spoorwegpolitie#Opgehev...
[2] https://nl.wikipedia.org/wiki/Politie_in_Nederland#Vorming_v...
Now the 21 regional police have been merged into one national police.
About a decade ago I was living in a major southern US city in the more modestly priced part of an upscale area of town. I came back to the area from work fairly early in the afternoon, rounded the bend, and saw both sides of the street littered with unmarked police cars and vans, with many, many extremely large men in suits and sunglasses running around, directing the hapless local cops to do this and that. I'm talking the whole American militarized authority jamboree and then some: dogs, rifles, lights flashing, citizens being shooed away. A big SWAT-looking van poking out of a driveway. Maybe 3 dozen official looking people all told. US law enforcement is nothing if not histrionic and self-important in how it occupies physical space, but this presence was more than just the usual overreaction to a cat stuck in a tree. I remember thinking "uh-oh" and really meaning it.
Of course I couldn't get into my parking lot -- I lived across the street a few doors down, and the cops weren't letting anyone through -- so I parked nearby and walked back over and began to chat up some neighbors, exchanging speculation on what the hell it could be. Obviously they were FBI, we all agreed - that's the cyborg-looking guys in suits, surely all grown in the same vat near Quantico? And the crime? Terrorism was the consensus, though one guy was sure it was counterfeiting money. (I remember that because he insisted that he knew someone "who used to do that".) The vibe standing there was equal parts morbid curiousity and real nerves -- what if someone was making bombs in our quiet residential neighborhood?
After a while someone got up the nerve to ask one of the bewildered local cops what the heck was going on. "That's not the FBI," he says, "that's the US Postal Police." Apparently someone was "sending marijuana in the mail".
This effing country, right?
I would even go so far as to say, there shouldn't be specific immigration cops, or alcohol, tobacco and firearms cops, since if there were actual crimes committed by immigrants or gun owners, the crimes themselves should be dealt with. To allow cops to go snooping around by widening jurisdictional responsibility, it has a very "pre-crime" aspect to it, which is often subject to prejudice and bias.
Maybe I'm missing your point, but isn't that exactly what the cops in question are supposedly doing? "Immigration cops" investigate illegal immigration. The ATF investigates the unlawful use or sale of firearms and drug trafficking. All of these things are crimes (regardless of whether they should be).
So how is there a "pre-crime" aspect to specialization among police when it comes to things that actually are crimes?
If the same resources that were dedicated to the numerous policing agencies in the US were given to a smaller number of more generalized agencies, those agencies would be allowed to prioritize where their time and resources are best spent protecting the public.
These people have a monopoly on legally sanctioned violence. If you think there is any merit in anti-trust for businesses or that big tech should be broken up, I hope you’d think it even more strongly for policing.
We don’t have a perfectly functional representative process, but we sure do have a way to get influence over the system. Imagine how much resources could have been devoted to the war on drugs if the police could have stopped all other policing. That would be terrible IMO.
It would also be bad (though perhaps less so) if the Dept of Education had no resources to examine its operations for fraud and waste.
If the counterargument is that these "crimes" shouldn't actually be crimes, then the solution is to remove the laws, no?
But I suppose that whether removing the laws is feasible is another can of worms.
If you trust the police to decide how to distribute their resources, I have some pretty bad news for you.
No relationship other than being impressed with the work.
https://www.amazon.com/Cuckoos-Egg-Tracking-Computer-Espiona...
One centralized Federal Police Department would be a single point of failure and bureaucratic nightmare.
Imagine if there were not State and local police departments. Just the FBI managing every shoplifting arrest in the country.
France and Sweden are both far more centralized and less federalized. There's a reason more federal countries such as Switzerland or Germany have more decentralized policing. I think it would be beyond unacceptable to most Americans, myself included, for the US to have a single police department with its bureaucracy in Washington. If anything, I think far too power in the US is already centralized in DC which contributes to bad governance due to the vastly increased distance (in many senses) between politicians and their constituents.
I would be fine with 50+6 state/district/territorial police departments, which is sort of the Germany or Canada (with Ontario and Quebec) approach.
And France and Germany are each twice as populous as the most populous US state.
So you're not really correct.
There's absolutely no reason why having a single bureaucracy wouldn't work well.
It actually seems like it would be much easier to have a single bureaucracy.
The US often seems to have more layers of administration and law-making than some other places. Making individual officers work through which set of powers and laws they're dealing with in a given moment seems like it might at times be a daunting prospect. You could in theory organize them into a single bureau, but I suspect you'd inevitably wind up with specialized sections to deal with the particular laws in given cities.
Private universities, same as public, may have Campus Police instead of Company Police, and those officers also have jurisdiction on public ways passing through the campus. In some cases they also have one mile extraterritorial jurisdiction; moreover, they can receive broader jurisdiction through agreements with the city/county law enforcement.
Railroad police are to be certified in their home state and have nationwide jurisdiction by federal law, on the property and rights-of-way of their employer as well as in connection with its services (conceivably quite a wide scope as railroads run right through virtually all major cities--the CPD "bait truck" incident that cause controversy a few years ago involved NSRR Police). With the exception of Amtrak, these are all private companies.
I'm not sure to what extend qualified immunity does or does not apply to them, however.
PA definitely has something like this too.. just like in NC, it originated from company towns, in their case mining.
Someone's never been mugged on campus before... Campus PD exist to give special protection to the children of wealthy upper-middle class families that thw surrounding community is usually deprived of.
That's a really charitable way of saying "handle petty stuff that the FBI can't justify spending resources on".
Every specialty police department exists for this reason and this reason only. Because the mission is often so petty they wouldn't get any resources if it was obvious that resource allocation to that task was resource allocation away from other policing.
When you have real problems the real police have no problems allocating resources and whipping up dedicated teams. When you feel like using state violence to harass drunken college kids you create a campus PD. When you feel like using state violence to kick the homeless out of the train station you create transit cops. Etc. etc. Even if you're an investigative agency you will have no problem getting the local cops to provide muscle if your needs are legitimate. "Look at us working with the <pick three letters>" is the kind of photo op local departments love, so long as it reflects well on them.