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But that’s one job Montgomery County police always take on at this time of year, when the fair opens up. As many as 300,000 fairgoers are expected to come to the Gaithersburg fairgrounds during this year’s event, which runs through Saturday. For all the money spent on win-win staples like cotton candy and corn dogs and rides on the Ferris wheel, a whole lot more will be lost at the gaming booths.

Even if you didn’t grow up attending fairs, it seems fairly harmless that a kid would pay $1 to attempt to flip a pingpong ball into a cup to get a goldfish a regular fairground attraction or $2 for a chance to dump an abusive Bozo in the water. But it is something entirely different to learn that a sober adult would spend most of a night, and probably most of a paycheck, throwing darts at balloons, or balls at bowling pins, all in pursuit of a Winnie-the-Pooh doll so big that it wouldn’t fit in the family truck anyway. It just seems wrong.

Sometimes, it is wrong. That’s when the cops come in.

Montgomery County’s finest take the unusual step of going undercover at the fair each year. The cops don’t dig for evidence of drug trafficking or prostitution or any of the odious crimes that fall under their division’s bailiwick before and after the fair. No, the police sleuths walk the beat on the 59-acre fairgrounds mainly just to ensure that vendors let everybody know that the Winnie-the-Poohs won’t come off the rack without a fight.

Talk about long odds.

“Really, the best we can do is make this a buyer-beware situation,” says Detective John Sheridan of the Special Investigations Division of the Montgomery County Police Department.

SID officers came to the grounds even before the fair opened to talk with S.M.S. Amusements, the carnival company that controls the midway and sold booth space to the 36 independent contractors running games at this year’s event. Some whole categories of diversions are banned: Games of chance and games where money is the prize such as the Bulldozer are prohibited by Maryland’s gambling statute.

Some games that are billed as games of skill are nevertheless verboten because the local cops have determined from past fairs that they’re a rip-off. The Lucky Strike Game, for example: This jewel calls for players to slide a coin or chip across a table and toward a pack of Lucky Strikes painted in the middle. If they get it to stop in the middle of the pack, they get the big doll. As simple as it sounds, SID detectives discovered that Lucky Strike booth operators lacquer the playing surface in such a way as to ensure that the pieces have no chance of landing in the winning area. The way things are rigged, the game might as well be called Throw the Money Down a Rathole. In past years, the cops shut the Lucky Strike Game booth down midfair; now, they don’t even allow it to be set up. You can still find the game in fairs in other jurisdictions, but S.M.S. doesn’t bother trying to bring it here anymore.

“We know the rules here, and we comply with them,” says Brad Thomas of S.M.S. Amusements.

He has had plenty of time to learn the local rules. Counting this year’s event, he’s been to 32 Montgomery County Fairs, all “with it,” as carny workers describe their status. Thomas, now 44, grew up in a family that traveled to work the fair circuit. As a youngster, he helped his dad run the Ferris wheel here. During breaks, he used to walk around the fairgrounds and spend some of his allowance for a chance at something big and fuzzy.

“I threw a lot of dimes at things back then,” Thomas recalls. “If I threw enough dimes, I’d win a prize.”

Thomas now manages a water park in Oklahoma during the summer. Since he works only five fairs a year, his two boys aren’t on as tough a traveling schedule as he was at their age. They’re not into playing fair games nearly as much as he was when he was at their age, either.

He himself hasn’t played any of the games that take up space in his company’s midway in quite some time “I’ve got all the stuffed animals I need for a lifetime,” he says. But Thomas still remembers the thrill of victory that he used to feel on those rare occasions when he hit pay dirt. And though he admits he’s a little biased now, he says it’s not right to judge those who pay good money to try to beat the odds, however great those odds are.

“I know that everybody doesn’t understand the attraction of all this, but I really think I do,” he says. “It’s simple: It really is about the stuffed animal, trying to get the coolest stuffed animal. People will pay to play for the coolest stuffed animal they can get. A lot about the fairs has changed, but that hasn’t.”

And he also doesn’t think others should judge him for how he makes his living.

“I feel good about what I do. People are happy at the fair,” he says. —Dave McKenna