Pardon?
There are very few private campuses. And the campus "police" exercise their "police authority" over everybody who is on the campus. Not just those that live there.
But let's get back to the real issue. Why can't they just call 911?
You mentioned campus police.
And if you do not think that a private college campus is private, I invite you to walk around some evening trying to get into dorms. Its not as easy at it looks.
That said, if they wish to hire people who have been trained and accepted by a local police fore; and deputized (or whatever has to happen to make them more than rent-a-cops) and they wish to pay for it—who are we to complain.
Their police powers would not go beyond their stated locations.
Why wouldn’t they just call 911? The answer to that is obvious. How can you not understand response times and deterrents?
I live in a north eastern suburb. The cops usually get on the scene withing 5 minutes—which is great response time. Except that in the case of a shooting, its about five minutes too late.
If you live in a township or rural community response times are longer. Thus, the need for a “local” response team.
Its the same reason why high school football games have ambulances on the scene.