The question occurred to Alan L. Tharp of Raleigh as he walked out of his neighborhood Kroger, pushing a cartload of groceries:
"Are stop signs in shopping centers legal, or are they merely suggestions?"
Let's call them sensible suggestions. Ignore them at your peril.
Just the other day, Tharp was crossing the parking-lot lane in front of the supermarket, on the way to his car.
The lane was posted with stop signs on both sides of the store entrance. It was a clear command, he figured, that an approaching driver must stop for shoppers walking in and out of the store.
"I assumed the car was going to stop, and it didn't," Tharp said. "It didn't hit me, but it scared me a little bit."
Later he counted 10 cars driving past the Kroger door; only one bothered to stop. Were nine out of 10 drivers breaking the law?
Before I consulted Kevin Lacy, chief traffic engineer at the state Department of Transportation, I thought the answer was clearly "No."
But Lacy clicked through one statute after another and declared the issue "clear as mud" - or clear as something traffic engineers call MUTCD.
You won't get a traffic ticket if you run a shopping-center stop sign, but you might get into an accident. And that will get you into trouble.
"I would encourage folks to stop for that sign," Lacy said. "If you happen to hit one of those people in the parking lot and you didn't stop, there is little doubt that you'd be held liable and responsible.
"Whether you get a ticket or not will be the least of your worries."
All North Carolina traffic laws are enforced on public streets and highways, of course. And some of them extend to private property, too.
"Public vehicular areas" include any private road, driveway or parking lot used by the public for driving.
Laws that tell you not to speed, drive drunk or text behind the wheel all are written to include these private areas along with the public streets.
But public vehicular areas are not mentioned in the law that tells you not to run a stop sign. It says only that government agencies are authorized to post stop signs and traffic signals on public roads.
Does that settle Tharp's question? I wish.
It turns out that the laws written in our legislature are not the only controlling authority. Here's where the waters are muddied by MUTCD - the Manual of Uniform Traffic Control Devices.
MUTCD is one of those things the Road Worrier reads so you don't have to.
Legislatures here and in other states have adopted MUTCD as a shared rulebook, to cut down on chaos when we drive cross-country.
Traffic laws vary a bit from state to state, and North Carolina law diverges from MUTCD standards. But wherever we go in the United States, for example, we know a green light means "go" and a red octagon means "stop."
The muddy part is that, unlike North Carolina statutes, MUTCD also authorizes private property owners to erect signs for "regulating, warning, or guiding traffic."
Instead of public vehicular areas, MUTCD speaks of "private roads open to public travel." But - and here the mud thickens - these are defined not to include parking areas or "driving aisles within parking areas."
So ... there isn't much enforcement power behind those stop signs in the Kroger parking lot. But stopping is a really good idea.
"I would encourage folks to follow the signs," Lacy said. "If there's an accident, there's any number of traffic engineers and lawyers who will tell you you had a duty to stop."
Meanwhile, remember this on your way out of the shopping center: The law treats parking lots, big and small, as private driveways where they meet public streets.
When you exit a driveway, you're required to yield to traffic in the street - whether there's a stop sign there, a yield sign, or no sign at all.