Heymatt:

When we cross the border at San Ysidro, my husband always comments on how excited the drug dogs look when they're sniffing all the cars. He thinks it's because the dogs are drug addicts, and that's how they get them to search. I'm not sure if he's serious or not, but I find it hard to believe. What's the truth?

-- Liz, Pacific Beach

Urban Legend No. 475, I think this is. On the same list with the giant alligators and nuked poodles. No offense to your mate, Liz, but a person would have to be a bonehead to think that a strung-out German shepherd would be of any use to anyone. Are drug-sniffing dogs addicts? Just say no. But according to one local dog trainer, it's a very widely held belief.

Here's an excerpt from my forthcoming book Drug Dog Training for Dummies. First, take one dog. A shepherd, retriever, spaniel-- working or hunting dogs are best. Shelter dogs are sometimes recycled as narcs. Now find out what turns this dog on, toy-wise. It could be a ball or an old sock, f'rinstance. Then administer the all-important personality test. Hide the toy, then see if the dog hunts maniacally for it until he finds it, returns it to you to hide again, and pesters you to continue playing this game until you want to strangle him. In short, would this single-minded mutt make a profoundly aggravating house pet? Yes? There you go. The perfect candidate.

Next, hide the ball about 500 times and praise the heck out of him every time he finds it. Now that he's "ball hot," as they say, one by one introduce the smells of the drugs you'd like him to find. You establish a connection between the ball and the smell-- and only the smell. The dog never comes in contact with the drugs. Pretty soon the dog should be just as eagerly hunting for the source of the drug smell, which he now associates with the ideas of ball-play-fun-reward-"Good doggie!"There's still some fine-tuning to do before he's ready to work, but those are the basics. So no wonder drug-sniffing dogs wag their tails and look so excited. To them it's just a big game with lots of praise at the end. A dog's favorite things. Mine too, for that matter.