Life can deal you a pothole or two. Ron Smith of Manassas hit one recently that felt as big as a crater.

He and his wife, Sally, are trying to sell their 1978 Chevrolet van. The Smiths posted a hand-lettered sign in one of the van's windows, asking $800 and listing a phone number.

Ron drove the van to Manassas Mall one day to do some shopping. He parked in the lot outside Sears. By the time he returned a few minutes later, the van had been towed away.

Ron's offense: advertising a vehicle for sale in a shopping center lot.

No, Ron wasn't actively hustling up a sale. He didn't hire pretty girls to beat tambourines and dance around his vehicle. Still, the sign in the window was enough to unleash the might of the criminal justice system.

The Smiths had to pay $85 to retrieve their van -- more than 10 percent of its value. They are now trying to sell it via the newspaper, bless their hearts. No luck so far. Did they long ago remove the sign from the van's window? Do you even have to ask?

So far, this looks like a case of simple injustice. But the full truth, as usual, is far more complex.

What Ron Smith ran into was an 18-month-old legal and anthropological tangle.

Unbeknown to him, when he parked outside Sears, he parked on a piece of tarmac owned by Sears, not by Manassas Mall. Sears and the state of Virginia have been tussling over freelance sales in that lot since Sears occupied its store at Manassas Mall in March.

The lot outside the Sears store was "like a flea market," according to Mynga Pham, the manager. Montgomery Ward had closed at the Sears site a year earlier. It didn't take long for independent buyers and sellers to discover that the lot was a) available and b) convenient.

In August 2001, when Mynga took over the store, she had a visit from W.O. McClam, a senior special agent for the Virginia Department of Motor Vehicles. He cited state law:

By "offering to display or permitting the display" of vehicles for sale, not only were citizens like Ron Smith on the wrong side of the law, even though they were passive sellers. Mynga was, too, for not stopping it.

Not surprisingly, Mynga says she has been enforcing a no-sales-in-the-lot policy since October 2001. The lot is liberally posted with warning signs. Apparently, Ron Smith didn't notice them or pay attention to them the day he fell through the looking glass.

How bad had things gotten in the days between Ward's and Sears? Mynga said she and Brother McClam pulled up a chair during Christmas season 2001 and watched the lot for a day.

They saw 60 to 70 for-sale signs aboard assorted merchandise. They saw people hawking cars, beer cans, tires, batteries.

W.O. told her to stop it or she'd be liable for a year in jail and a $2,500 fine. As the young folks would say, that one was a duhhhh!

Alice Jones, general manager of Manassas Mall, said most people "don't understand that it's illegal" to do what Ron Smith did.

However, as Alice noted, it's no surprise that the flea marketers arrived in force once Ward's departed. The lot outside that store "has lots of depth," Alice said. It fronts on Route 234 "with a complete clearing." And there is "complete visibility from the lot to the highway."

But the law is the law. Sears landed so hard on Ron "because they are required under law" to do so, Alice said.

Let this be a warning to shoppers who drive vehicles to malls and forget for-sale signs in the window. Forgetting may be very, very expensive.

The 30-minute rule, born after Sept. 11, is still in effect for flights using Reagan National Airport. You can't get out of your seat to go to the bathroom if an outgoing flight is in its first 30 minutes or an incoming flight is in its last 30 minutes.

The idea was to decrease the likelihood of another hijacking. But the real effect has been:

1) Zero increase in meaningful security. Preventing someone from going to the bathroom for 30 minutes at the beginning or end of a National flight is punitive, not protective.

2) Major increases in discomfort. People need to visit the loo for many reasons, every day. Why make thousands pull in their tummies and count to 10 because of one horrible day?

3) A trickle of desertion. The 30-minute rule is inducing me (and some readers) to avoid National, despite its convenience. There's no 30-minute rule attached to flights into or out of BWI or Dulles.

Three months ago, I wrote that the 30-minute rule has to go. If you do the security job on the ground, you don't have to do it again in the air. Return bathrooms to the populace, I urged.

But don't take the word of customers. Professionals think the 30-minute rule is ridiculous, too. One of them, a US Airways captain, wrote to me recently to make two points.

First, although the rule is "laughable," it's probably here to stay.

Second, there are ways to make a midair appeal effective. Here's what this pilot advises:

If you have to go to the john, don't be afraid to tell a flight attendant. But if you get the okay, use the restroom to the rear of the plane. If you head toward the front of the plane, that would be "very poor judgment," says my guy.

Also, "have nothing in your hands, no shoulder bag, no book, no paper. Your intention should be crystal clear."

I'm still not abandoning hope that this oppressive rule will bite the dust. But until it does . . . thanks, captain.