Originally Posted by Spiffy
and you can still get a ticket in the parking lot of a private business because the parking lot is a public space...
Perhaps in other cities but in Portland probably not.
I say "probably" because I base it on what an actual Portland Police Officer
told me while I was working as an Oregon licensed Unarmed Security Guard.
At an unnamed location the customer (security is generally a 3rd party service) wanted us (the security guards) to enforce the stop sign at the exit to the property. This was a very old site and most of the employees had worked there for over 20 years; no one was going to stop without tangible consequences. Unfortunately the customer was unwilling to penalize their employees and we had no way to stop these drivers other than to jump in front of their automobile and hope they stopped.
Of course nothing changed but as a contracted service provider we have to try to acquiesce to the customer's demands.
One day a PPD traffic enforcement cop was parked immediately outside our site and it not being busy I chatted him up on my conundrum. He basically said that while an unsecured (not walled or fenced off) piece of property like a parking lot has a sort of "common law" public property status that PPD has no jurisdiction over street signs placed on private property by private entities that don't have traffic engineer degrees and could conceivably set up street signs for the purpose of entrapment. He sympathized but was able to direct me to some statutes that backed up what he said. Naturally I can't remember anymore what they were.
Of course this wouldn't stop a cop from writing "Too Dangerous for Conditions" tickets for blazing in and out of risky areas too fast but they require more effort to defend on a traffic-court-dismissal basis than a simple "20MPH or over" speeding ticket with laser speed gun telemetry. This also doesn't stop the police from issuing a ticket on private property for infractions on public roads; they are encouraged to pull drivers over somewhere safe and legal. Barbur is arguably less safe than any of our interstate highways for a cop executing a pullover. Parking lots seem reasonably safe until you remember that most people treat them like anarchy zones.
I'm hoping for either the self driving cars that will avoid pedestrians as flawlessly as Google's does in this video
or red light cameras and unmanned speed traps everywhere that will free up police to actually enforce the more fuzzy interpretive parts of traffic law.