You know that feeling you get when, as you’re cruising peacefully down the road, you’re jolted by the flash of red-and-white lights in your rearview mirror? When you look at the speedometer, your stomach sinks and you realize, “Damn, I’m snagged”?

I miss that feeling.

That’s because I live in Olney, where the judgment of police officers has been replaced by Camera 1329 — one of the top-performing (and revenue-generating) speed cameras in Montgomery County.

If you think speed cameras catch only reckless drivers, then this suburb that real estate agents pitch as “family friendly” must attract the most dangerous drivers in the Washington area, according to county police data. Each year, the camera on Georgia Avenue vies for first place in the county in tickets, dishing out more than 31,000 in 2010. Three more cameras guard two roads that lead to and from our town; together, these four mechanical cops nabbed more than 97,000 maniacs at the wheel last year.

It’s a wonder that the streets of Olney aren’t littered with human roadkill. But many of us who’ve been nabbed think the success of these cameras reveals something else: Some of our speed limits are dishonestly low, and some of the cameras are set up in a sneaky way that turns reasonable drivers into violators.

Most Americans speed; 89 percent, according to a survey this year by Allstate. That doesn’t mean they all drive too fast. Traffic engineers recognize that drivers gravitate toward speeds that most of them feel are safe regardless of speed limits, and that their collective judgment is credible. That’s why engineers suggest following the 85th percentile rule, which the Maryland State Highway Administration defines as “the speed at or below which 85 percent of the motorists drive on a given road when unaffected by slower traffic or poor weather.”

The highway administration calls this “a good guideline for the appropriate speed limit for that road.”

Montgomery County doesn’t use this guideline before putting up a speed camera. Consider the process for installing the camera at location 1329 in Olney. It’s instructive for anyone who passes any of Montgomery’s 100-plus cameras.

A speed study found that 47 percent of vehicles exceeded the 30 mph limit by at least 12 mph. That’s the threshold for the cameras to click. The study did not count those who exceeded the limit by lesser amounts, although the police official who provided the figures noted, “I guess there were a lot traveling 30 to 40.” Clearly, a large majority of drivers simply confirmed the observation of a 1992 study by the U.S. Department of Transportation: “Motorists ignore unreasonable speed limits.”

Rather than rethinking a speed limit that most drivers consider unreasonable, however, the county installed a camera to punish them.

So the success of this camera is predictable. That success exposes not a population of menacing drivers but a dubious speed limit and devious camera placement.

State law restricts speed cameras to residential areas and school zones. Authorities pitched the cameras as a way to protect children and people trying to cross their own streets. Yet we commonly find the cameras on busy, four- and six-lane roads, in areas that are commercial or sparsely developed.

Here’s how authorities pull this off: Our main camera in Olney points north on four-lane Georgia Avenue into the business district, catching people as they enter several blocks of gas stations, supermarkets, offices and fast-food joints. The camera’s speed zone sits in front of the second-to-last house before those businesses start. Behind the camera are two blocks of homes. But the camera aims away from the houses; it catches people who fail to slow down for a bank.

We see such trickery elsewhere. In Kensington, one camera stands on each side of breezy Connecticut Avenue, where the six lanes are divided by a grassy median. A temple sits off-road behind the trees; it includes a school. Gaithersburg put cameras on a predominantly commercial strip of Rockville Pike where, despite six lanes, the limit is 35 mph, then 30. The cameras stand ahead of an intersection for a street that leads to a high school.

Good drivers feel cheated when caught by cameras in such places. They are not flying recklessly past homes and schools.

Cops know that. The social contract of the road has long been that police usually pull over the egregious offenders, those who knowingly push the boundaries. Even those offenders usually get the chance to offer a justification (or at least an entertaining tale).

The cameras remove that human judgment. They snag safe drivers who can honestly say, “I was speeding, but I wasn’t wrong.” We long to tell that to a cop.

The writer is a former editor of AAA’s “Car & Travel” magazine.