Bill Mata is now off the hook. But for a while there, he was up to his ears in a major mess that didn't look as if it was ever going to end.

About 11:45 p.m. on Oct. 2, in Portsmouth, Va., a car smashed into three others. The three motorists whose cars were struck jumped out to inspect the damage. Moments later, the driver who had run into them took off. As the hit-and-runner left the scene, his three victims got a good look at his license plates -- or at least they thought they did.

They told the police, and their lawyers, and their insurance companies, that the second letter on the Virginia license plates of the fleeing driver was a V. So a few days after the accident, Bill Mata began to hear from various lawyers and insurance agents who wanted to know why he had committed a felony Oct. 2 in Portsmouth.

Of course, it was a case of mistaken identity. Bill lives on Mason Neck in Fairfax County, not far from Washington. He has never been to Portsmouth, which is near Norfolk, several hours' drive from Mason Neck. He most certainly has never fled the scene of a car accident.

Bill does indeed possess the tags that the victims claimed to have seen. However, after the Portsmouth police checked further, they discovered that only the first, third, fourth, fifth and sixth digits on Bill's tags and the hit-and-runner's tags were identical. The V that the witnesses thought they had seen had really been a U.

It took the authorities more than a month to establish that. In the meantime, Bill was insulted, investigated and threatened. It wasn't until last week that he received apologies and all-clears from all concerned.

Bill is more sanguine about the case than he might be. "Just one of those things," he told me.

But what if it was just one of those things that left a permanent scar on Bill's driving record? What if he discovered that he couldn't renew his tags or driver's license because of a police investigation that no one had ever bothered to cancel officially?

Jeanne Chenault, a spokeswoman for the Virginia Department of Motor Vehicles in Richmond, said it's unusual for a case of mistaken identity to produce a lasting blot on someone's official driving record, especially if charges are never filed. However, Jeanne said it's always a good idea in a case like this for an innocent victim to check.

For less than $5, Bill can obtain a written copy of his driving record by calling, writing or walking into any DMV office in the state. If any errors appear, Bill can write to DMV and request that his record be cleared. He should be sure to enclose copies of all letters from lawyers and insurance companies.

In the meantime, lawyers and insurance agents should be sure to write letters of apology, quickly, in cases like this. After all, they could be on the wrong end of the stick just as easily as Bill Mata was.

Stephanie Cutler, of Northwest Washington, got ducked the way so many Washingtonians get ducked every day. She tried to hail a cab in downtown Washington to take her to an appointment in Northeast. But as soon as she stated her destination, one driver after another refused to take her. One excuse was more transparent than the next.

There's a legal remedy in such cases: Take the driver(s) before the D.C. Taxicab Commission. Alas, that takes time and perseverance. Most passengers who have been discriminated against figure it's not worth pursuing.

But Stephanie asked for a hearing and turned up on the appointed day (which fewer than 10 percent of the people in her shoes do, according to the commission).

The process took about two hours from start to finish, about one-third of the average time it takes to fight a parking ticket. Best news of all: The cabdriver was socked with a $250 fine and a warning that the next offense could lead to a suspension.

Stephanie's bottom line on the experience is fit for framing. "Bob," she writes, "please tell people using cabs in our city that they have a duty to report, and to follow up by prosecuting, violations in cab rules."

Martin Buxbaum, of Bethesda, says several close friends needed loans. But as soon as Bux laid out the cash, he never heard from the friends again.

He figures that this sort of friendship is based on the old saying, "Till debt do us part."

Great moments in modern life:

One recent evening, a Dad came to pick up his pre-teenage son, who had spent the afternoon playing at the home of a friend after school. Dad pulled into the driveway, picked up his car phone, called inside and asked the Mom to please send his son outside.