I recently took my boys (11 and 3) to a pen shop and while we were talking with the salesman a man came in.

After a few minutes he said he thought he'd had his wallet with him when he entered the store. He then turned to my older son and said, "Do you have my wallet?" We were obviously shocked so the man said to me, "He brushed up against me. Would you see if he has my wallet?"

He demanded that I search my son's pockets. When I refused, and refused to ask my son if he had taken the wallet, the man insisted that we stay in the store while he looked in his car.

Instead, I left my sons there and went across the street to my own car to tell my wife what had happened. The man met us on the sidewalk and said he was a police officer, detaining me until his wife -- who he said was also a police officer -- could call a patrol car. He said his identification was in his wallet; she didn't offer hers. (It later turned out that he had a security job and she worked for the police department, but neither were police officers.)

The man kept insisting that I search my son and that if no wallet was found, he would apologize, and if he found his wallet later, he would call with an apology. He gave me his name and number; I gave him my card.

When the policeman came, I told him that he would have to follow police procedure because I wouldn't search my son or ask if he had taken the wallet.

My wife asked what rights the boy had and the policeman said he had no rights; then he said that he would read my son his rights after he had been searched at the precinct. Suddenly, the officer changed his mind and told my son (who was mortified by then) to "empty your pockets." There was only a tissue. The officer reached into the boy's pocket to make sure and then turned him around and patted him down.

He then gave me his card, made a few notes and left, making no apology then or since. Neither did the man who accused my son, even though he later told the police that he had found his wallet.

I asked the police department to investigate the handling of this case and eventually was told that 1.) the policeman said he hadn't searched my son but only patted him down, and 2.) the officer handled the situation "according to police procedure."

My wife and I have used this experience to talk about legal rights. I do everything I could to protect my son?

You gave your boy the kind of protection that counts: You stood up for him. You demanded his legal rights. And by asking for an investigation, you let your son know that every citizen, even an 11-year-old citizen, has rights. You couldn't have given him a better lesson in civics.

The incident and the subsequent department investigation gave him a more basic lesson: in reality.

Unless a situation is explosive or well-documented, a police force generally defends its own, at least in public, even though it may chastise the policeman in private. If you talk about it with your son, you'll find he can understand the impulse behind that kind of loyalty. He would be slow to squeal to a teacher on the shenanigans of a classmate who had gotten the whole class in trouble, but he might tell him off on the playground.

Your son also got a good lesson about human nature. From now on he knows what you've known for years: There are incompetents in every profession. And your son will not forget your example on how to handle a confrontation.

This kind of knowledge is invaluable. The child who learns how to grapple with problems -- and problem people -- in an adult way can defend himself in later incidents.

There may still be a few bad shopping experiences ahead for your son. Because preteens and young teen-agers often shop with a friend or two, they invite the attention of security guards. It's easy to suspect young shoppers who usually have little money to spend, hours to browse and an urge to touch everything they see.

It would be wise if your child -- and all junior high shoppers -- limited their browsing time and left at home their big coats and shopping bags, both trademarks of the shoplifter. There's no sense in courting trouble.

But in case trouble does come, parents -- and their children -- will be protected better if they've read the American Civil Liberties Union's revised edition of its handbook, "The Rights of Young People" by Martin Guggenheim and Alan Sussman (Bantam; $4.95).

A good book teaches a child well; a good parent teaches him better. By standing up for your son, you've taught him how to stand up for himself. Now he can put a bad -- and unusual -- experience behind him. And so can you.

Questions may be sent to Family Almanac, P.O. Box 15310, Washington, D.C. 20003.