Speed Traps: What Police Officers Use to Catch You
By KEVIN RANSOM, AOL AUTOS
What to Look Out for:
?Good old-fashioned radar: method of speed detection you know and loathe

?Laser Guns: same technology, but more accurate than old-school radar

?Aerial Detection: a more cunning way to catch you

?Speed Cameras: You won know what hit you until you get the mail



Of course no one likes getting a speeding ticket, and who hasn't cried out, "You gotta be kidding me!" upon learning that a heavy foot just lightened your wallet by $150 or $200? But the sad truth is, the best way to avoid that kind of a bite is to just slow down, because police officers -- whether they be city cops, state troopers or county sheriff's deputies -- definitely have technology on their side.


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At this point in the history of highway driving, everyone knows that the most popular police speed traps employ good old-fashioned radar. In this scenario, of course, a police officer will stealthily park his or her patrol car out of the view of oncoming motorists, perhaps under an overpass, in a ditch in the middle of the freeway or behind a billboard.

Then, the police officer will flip on a radar unit that transmits radio waves at particular frequencies. The waves bounce off the target, in this case, a car that the police officer thinks is speeding, and those waves are then picked up by a receiver. The shift in frequencies tells the police officer how fast the car is going.

In recent years, however, more and more police departments have been using laser guns, either in addition to or instead of radar. "We began using the laser guns about 10 years ago," says one former police officer from a midwestern state, who asked that we not use his real name. We'll call him Jack.


" Then, there will be a 'spotter' in a police copter or plane, and he can calculate your speed ... "

"They're actually more efficient than radar. The laser guns can pinpoint a specific car much more accurately," says Jack. The other advantage to using a laser gun is that the laser light can't be detected by those pricey radar detectors often used by drivers who would really rather speed with impunity -- or is that immunity?

One of the more sly methods that police officers use to detect hot-footing motorists is aerial detection. In many cases, this is done by painting lines across a quarter-mile or half-mile stretch of highway. "Then, there will be a 'spotter' in a police copter or plane, and he can calculate your speed based on how many of those lines you pass over while driving along that stretch of road," explains Jack. "He can then just call ahead to an officer in a patrol car on the ground that's another two or three miles down the highway, and tell him, 'green Taurus, left lane.'"

In another aerial speed-detection technique, the spotter simply does a visual estimate of the speed of the cars below, and compares it to the "ground speed" of the helicopter based on using visual targets along the highway.


There is yet another method to catch speeders, and it doesn't require a police officer to be physically present at the speed trap location. Speed cameras are attached to lampposts or telephone poles and are programmed to snap photos of speeding vehicles. While speed cameras have been employed on a comparatively limited basis in the United States, they've been used more extensively in Europe, Canada and other parts of the world for more than 30 years, according to the Insurance Institute for Highway Safety.

This method can deliver a delayed shock to the system of a speeder, since the driver isn't pulled over on the spot. He won't know that he's gotten a speeding ticket until he receives the eye-popping infraction notice in the mail. If you have a problem controlling your tongue in the presence of a police officer who has just written you a $200 speeding ticket, this ticketing system might be your favorite.

Sometimes, the best enforcement of speed limits is a not-so-subtle reminder in the form of the electronic speed boards you see alongside a highway that flash big, bright, white-hot numbers in your face to let you know how fast you're going. These boards also employ radar.


" That a myth that we had quotas on how many traffic tickets we had to write in a single month. "

"The radar unit sees the target, transmits the radio waves, they bounce back, and tell the drivers how fast they're going," says Jack. "We used to think of those speed boards as being more of an 'awareness program,' because they reminded people how fast they were going. A lot of drivers really don't know how fast they're going, so these speed boards essentially are a means of urging voluntary compliance."

And, according to Jack, that's the main point of enforcing speed limits via speed traps. While traffic fines do augment revenues for the city, state or country, that's not why speed traps are set up, says Jack. "That's a myth that we had quotas on how many traffic tickets we had to write in a single month. We just want people to obey the speed limit, because it's for their own safety," says Jack. "The main reason for setting up a speed trap, whether it's radar, laser or aerial monitoring, is simply to encourage voluntary compliance of the law," says Jack. (Ed. Note: We are working to clarify this statement in response to emails our readers have sent us stating quotas are used in their areas. It is possible quotas are enforced in some states or districts and not in others, like Jack's.)

"And we never cared if someone called in a radio station and says, 'Oh, there's a speed trap set up on such-and-such a road,' because it achieved the same result as a motorist seeing a cop writing someone a ticket. It got people to slow down."


See Also: Ticket Avoidance Tips