Recently I have heard it from several sources that cops must have their headlights on at night if they are speed trapping.
This reeks of the UL where it is believed that undercover cops must identify themselves if asked directly.
Any cops or lawyers out there with the Straight Dope?
In California, speed enforcement by the use of a speed trap is strictly against the law.
I guess it would be prudent to ask, for the purposes of the OP, what’s the definition of a “speed-trap”? I can’t imagine that a patrol car sitting along the side of a road(be it hidden in bushes, behind a billboard, or what-have-you) can fairly be considered a speed-trap. I mean, why? What’s the trap? If you’re exceeding the legally posted (as in, its posting is legal and not itself a trap), speed-limit, and you get caught by a hidden patrol, that’s your fault. They didn’t do anything to coerce you into breaking the law.
On the other hand, if they somehow manipulated things such that you broke the law unwittingly, that could be a trap. Can’t think of any good examples offhand, though.
FYI - I do break the law in the speeding respect; I just try to be careful.
I dont know if there is any law pertaining to it. Some agencies might have this rule in their official policy, but none that i’ve ever heard of. I have seen police cars using their radar with headlights on, with parking lights on only, and quite a few with nothing on at all. I think it pertains to safety. If the police cruiser is well out of traffic’s way, there is no need to illuminate any lights. However, the greater safety concern, the more safety the officer is going to take. So if the cop is sitting right there in the median, he is probably going to have some lights illuminated.
Back when I was a radio repairman, one of the local PD’s that I did business with had me install headlight cutout switches on all the cars…not both headlights, just one. If people see a car with one headlight they naturally think it isn’t a cop.
The California Vehicle Code defines a speed trap in §40802. It bans them in §40801. §40802 contains some of the most complicated nesting of parts, sub-parts, sections and subsections I’ve ever seen, and is clumsily formatted to boot.
However, what I think it’s doing is (generally) defining a speed trap as one of two things:[list=1][]Any kind of clocking of speed by measuring elapsed time over a known distance (commonly done with aircraft)[]Using radar on a stretch of road where the speed limit is set below that justified by an engineering and traffic survey[/list=1]The second instance is fine - no setting the speed limit far lower than is reasonable just to raise revenue. I’m curious as to why aircraft observation is illegal in California, though, and by what stretch of the imagination it deserves to be called a “speed trap.”
Because an airplane with a radar gun can circle the area for hours, radioing ground crews when someone is speeding. The crew on the ground never actually clocks the person or takes any reading, they just pull over and ticket who they’re told. There is a strong chance it will be a false reading or the wrong person will be pulled over. And since the cop issuing the ticket didn’t take the reading, he cannot testify in court that you were speeding, it would be hearsay.
–Tim
I understand those arguments, Tim, but they sound pretty flimsy to me. (I don’t have detailed knowledge of just how aircraft speed surveillance is done in states where it is legal.)
From what I understand, the aircraft doesn’t use radar. It measures the time it takes for a vehicle to travel between two paint markings on the pavement, and divides distance by time to arrive at an average speed.
The air crew then radios down to a ground unit, “Yeah, we got that black Camaro doing 85 over the last interval. He’s passing you…right…now.” The ground unit then pulls the guy over and doles out the ticket. The air crew might even follow the chase to ensure that the right car is pulled over.
Perhaps they can/should bring both the ground and air officers into court. The air officer maintained positive visual contact from the time of speed determination until the ground unit pulled the car over, so he can verify that the ground unit got the right car. The ground officer testifies that the guy in court right now was the guy driving the car. While some tortuous legal thinking may get this kind of tag-team law enforcement ruled heresay, I consider that pure BS (realizing fully that my opinion matters none at all).
I’ve heard the arguments against this sort of thing, and they all strike me as fantastic reaches.
By that argument, virtually every speed trap I’ve ever seen would be suspect. Typical setup: One fellow in a ghost car (or on a bicycle!) with a radar gun and 2-way radio, and a few hundred metres down the road, a second fellow on the other end of the 2-way pulling people over or not, and a further complement of squad cars with notepads at the ready. The person writing the ticket is almost never the person who held the gun. Why is an aircraft and some high-powered binoculars any worse?
One time I was driving along at the speed limit, when there’s this car right on my rear bumper. I sped up a little bit, he was still there. Sped up a little more, and guess what? It’s an unmarked police car! He stopped me and when he asked if I knew how fast I was going, I wanted to say I sped up because he was tailgating me, but I just apologized and said I didn’t realize my speed had crept up that much. He let me off with a warning.
I know of a stretch of road in SW Florida where the speed limit varies between 35 and 65 MPH, sometimes changing for just a few hundred feet. They often set up speed traps immediately after a 20- or 25-MPH drop. Would this count? It does get confusing when the signs are so close together.
V & D, I would assume the changes are not a speed trap, per se, as long as there is a valid reason for the speed limit changes. One stretch of road I know changes to 30mph in one small stretch because it is residential in that area. Other areas are more commercial, no houses, so the limit is higher. Of course, the local police are often sitting there waiting for speeders, and give out a lot of tickets. This is not a bad thing, IMHO, since drivers would cruise through there at 50 without batting an eyelash, if the cops weren’t around. Thx to the cops, people tend to slow down a LOT when they reach that stretch.
I saw the aftermath of an accident there between a little car and an oil truck, the little car was probably doing 55, the truck was probably stopped, delivering oil, I don’t need to tell you how ugly a scene it was.
OTOH, if there is no perceptable difference between the 65 stretch and the 35 stretch, that would sound pretty fishy to me.
The trap isn’t so much the sign as the officer waiting right behind the sign, rubbing his hands together in gleeful anticipation of the next ticket.
Let’s say for example that you are on a highway, and the speed limit changes from 65mph to 55mph. Let’s also say that you are one o’ them law abiding types, and immediately reduce your speed as soon as you notice the sign. Even though you are decelerating, there is a pretty good chance that at the precise moment you pass the sign posting the new speed limit, you are traveling faster than 55mph. This is when they pounce.
“Poppycock! Balderdash! A pile of crap!” say some. In fact, this was the precise reaction of my family, several years back, when I tried to warn them of a trap near my home that worked exactly as described above. Every now and then I like to remind them of their reaction, along with the fact that I am the only family member who never received a speeding ticket from this trap.
RiffRaff pretty much described the situation perfectly. And no, there is no real reason for the changes; the road is completely rural and there’s nothing around but cornfields and the occasional farmhouse. Some people I know got a $200-something ticket when the speed limit suddenly went from 65 to 40, and this was in an area without streetlights, so it was very easy to miss.
I was talking about any cop sitting somewhere and checking people’s speed. I had never even considered them setting actual “traps”
The California Vehicle Code defines a trap not in the sense of a snare, or a ‘gotcha’, but simply timing over a known distance. Similarly, at the end of a drag strip is a portion known as the trap, where the speed of the cars is calculated by measuring the time it takes for the car to cross the measurement area.