Rather than your straw man argument concerning "basically all human knowledge," let's stick with the more reasonable and rational issue that there's no excuse for law enforcement if they don't know the law. For example, I've heard cops say one thing, at which point I thought, "That doesn't sound right..." and upon looking it up, I discovered my hunch was correct.
The point is, where did I look that up? Did I peruse "all human knowledge?" Of course not. We cannot expect cops to know "all human knowledge." Furthermore, I submit that we can't expect them to know every local, state, and federal law pertaining to their jurisdiction, either.
That's why they're given General Orders, and they're told, "know these." General Orders usually come in two volumes, or "Manuals:" Administrative and Field. These days, they are usually provided online for reference by the public as well as other law enforcement agencies.
Here's a prime example.
Again, you're using straw man arguments to blow things way out of proportion. While the "innumerable" Internet is indeed unknowable, you're talking about a relatively minute microcosm of information surrounding driving through intersections. Having been in 33 different countries, I've encountered some wacky intersections, certainly far worse than anything that exists here in the U.S. Did I crash? No. Did I cause an accident? No. Well, why the heck not?
Simple: Sufficient training in high school driver's ed, a couple years of experience navigating U.S. roads, and sound judgement.
But I don't think the thread was referring to our knowledge of the law, but that of law enforcement.
When I flew airplanes for a living, I was given enough time to thoroughly study my regs. Knowing the General Orders through and through is central to a cop's job. It may not take top billing, but it's certainly up there.
And yes, they're usually available online, so for the cop, there's no excuse. If you examine SFPD's General Orders on
Investigative Detentions, for example, it's crystal clear as to the nature of their duties and limitations.
Use of Firearms is another good example.
As we've seen above, most of us can access our local law enforcement department's General Orders. If they're not online, ask them where you can obtain a copy. Law enforcement is allowed to violate them
only upon authorization from higher authority, or if they have a very good, rational reason for doing so, and as stated in many of the orders, "hunches" aren't one of them.
When it comes to responsibility, however, I have no responsibility, stated or implied, to know their General Orders. I am, however, responsible for knowing the rules of the road, including what to do at strange and unusual intersections.