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Radar Beats GPS In Court — Or Does It?

Soulskill posted more than 4 years ago | from the technology-deathmatch dept.

Transportation 369

TechnologyResource writes "More than two years ago in California, a police officer wrote Shaun Malone a ticket for going 62mph in a 45-mph zone. Malone was ordered to pay a $190 fine, but his parents appealed the decision, saying data from a GPS tracking system they installed in his car to monitor his driving proved he was not speeding. What ensued was the longest court battle over a speeding ticket in Sonoma county history. The case also represented the first time anyone locally had tried to beat a ticket using GPS. The teen's GPS pegged the car at 45 mph in virtually the same location. At issue was the distance from the stoplight — site of the first GPS 'ping' that showed Malone stopped — to the second ping 30 seconds later, when he was going 45 mph. Last week, Commissioner Carla Bonilla ruled the GPS data confirmed the prosecution's contention that Malone had to have exceeded the speed limit and would have to pay the $190 fine. 'This case ensures that other law enforcement agencies throughout the state aren't going to have to fight a case like this where GPS is used to cast doubt on radar,' said Sgt. Ken Savano, who oversees the traffic division. However, Commissioner Bonilla noted the accuracy of the GPS system was not challenged by either side in the dispute, but rather they had different interpretations of the data. Bonilla ruled the GPS data confirmed the prosecution's contention that Malone had to have exceeded the speed limit."

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369 comments

Standard Calculus (5, Insightful)

misosoup7 (1673306) | more than 4 years ago | (#30013290)

If the average speed is 45 mph, and he was stopped at the end (ie speed 0), then at some point he was going above 45. Especially since you can't stop instantaneously. This is like calculus you learn in High School... If the Judge ruled the other way, the future of America would be even in deeper sh*t than it already is.

Re:Standard Calculus (3, Informative)

olden (772043) | more than 4 years ago | (#30013320)

Seconded. Furthermore, even if the GPS averaged on a much smaller interval, quoting http://www.pressdemocrat.com/article/20081206/NEWS/812060371/1334/NEWS [pressdemocrat.com] :
"The distance between the radar reading and when he was recorded going 45 mph is great enough that Malone could have easily slowed down, Heppe testified."
Game over son, you lost.

Re:Standard Calculus (5, Informative)

pyr02k1 (1640167) | more than 4 years ago | (#30013342)

The problem of this calculus you mention wasnt the speed at the end, nor even the beginning. we're missing a piece of information to properly go through this. distance. it says at a stop light, he was 0, then the next ping was 45. but the problem becomes distance covered in that 30 seconds. tie in the math, etc. if it says 45 on the ping, thats worthless. we need to know how far he traveled in 35 seconds to get an average speed, and, for the sake of argument, his vehicles 0-60 speed as well to get the stats on how quickly he could have possibly gone up to 60, nearly where they "clocked" him. obviously, his average speeds worthless, and his speed 30 seconds after his initial of 0 is worthless. we need the distance traveled in that 30 seconds. And TFA says "virtually" the same location. For all we know, he spotted the cop, hit his brakes and was doing 45 when he was pinged. Distance is key ... notice how TFA forgets that wonderful detail. And, I'm sure as a teenager, with a GPS, he knew that if he hit 70, theyd get an email alert. Heck, he probably knew that if he wanted to, he could go 69, wait for a ping, if he had timed them right, speed up to 100 and brake to 69 again, all before the second ping... I guess the parents forgot that Teenager + Technology is generally > Parents + technology

Re:Standard Calculus (4, Informative)

Anonymous Coward | more than 4 years ago | (#30013392)

"It recorded Malone sitting at a stoplight at Frates Road and 30 seconds later going 45 mph 2,040 feet farther down the road, according to Heppe."

d=rt so we have 2040 = x * 30 so 2040/30 = x x=68!

Yep - GPS proves he was speeding.

Re:Standard Calculus (3, Informative)

pyr02k1 (1640167) | more than 4 years ago | (#30013416)

i only caught the part on the pressdemocrat link. missed a whole other link :D take one thing into account now, the rough 0-60 speed of a car, that can do 0-60 in 6.8 seconds. it would travel around 300 ft if the speed was exactly the same the whole distance to 60. thats the other part we need in this equation and we're golden. if it took him 300 ft to get to 60 at 6.8 seconds. he has 23.2 seconds to continue 1700 ft. so he'd of been doing, 73 :D now figure in his car was really slower then that, but 65 would be about right in the end result. no matter the year of celica, i doubt it was doing 0-60 in 6.8, unless mommy and daddy paid a load of cash to make it go faster... he sped. i think if gps proved he wasnt speeding, it'd of been nice. but they spent all this time fighting a case, where he was speeding anyways. oy vey

Re:Standard Calculus (1)

pyr02k1 (1640167) | more than 4 years ago | (#30013420)

oh, crap, and a side note. we're assuming the light turned green immediately after he was pinged at 0. if it turned green 5 seconds after that, it's even worse in his case...

Re:Standard Calculus (4, Funny)

Anonymous Coward | more than 4 years ago | (#30013454)

In a few posts, somebody will prove he even broke the sound barrier.

Re:Standard Calculus (4, Informative)

Dachannien (617929) | more than 4 years ago | (#30013440)

Actually, you did your math wrong. 2040 feet / 30 seconds = 46.4 miles per hour.

The thing is, that's the average speed over the 2040 feet. As was mentioned above, given the initial condition of v(0) = 0, this means that at some point in the intervening distance, the kid must have been going significantly more than 45 mph.

The final condition of v(30 seconds) = 45 mph would increase the peak speed even more.

Re:Standard Calculus (1)

ta bu shi da yu (687699) | more than 4 years ago | (#30013560)

Uh?

2040 over 30 is 68!

I'm sure I'm missing something here.

Re:Standard Calculus (4, Informative)

teg (97890) | more than 4 years ago | (#30013600)

2040 over 30 is 68! I'm sure I'm missing something here.

Yes, he is converting from feet over seconds to mph at the same time.

Re:Standard Calculus (4, Funny)

CarpetShark (865376) | more than 4 years ago | (#30013792)

Yes, he is converting from feet over seconds to mph at the same time.

Look, do you want the rigorous NASA method or not?
 

Re:Standard Calculus (1)

gander666 (723553) | more than 4 years ago | (#30013882)

Let's not get a metric conversion in this, ok?

Re:Standard Calculus (2, Informative)

Anonymous Coward | more than 4 years ago | (#30013602)

2040 ft / 30 seconds != 68 miles/hr. it equals 68 feet/second, which is 46.36 mph. Still speeding though since he was stopped at the beginning, so he couldn't have been maintaining that 46mph the entire time and would have to have gone faster than that. 46 mph is still speeding anyway ;)

Re:Standard Calculus (2, Funny)

bmr91 (1653939) | more than 4 years ago | (#30013614)

You missed the fact that the 68 is in feet per second. 68ft/1sec * 1mile/5280 * 60sec/1min * 60min/1hr = 46.4 Mile/Hr Come one, that's just standard unit conversion.

Re:Standard Calculus (1)

Paradise Pete (33184) | more than 4 years ago | (#30013622)

I'm sure I'm missing something here.

When you get to 68, keep going. Your arithmetic is not done. 2040 is not miles, and 30 is not hours, so that 68 does not represent miles per hour.

Re:Standard Calculus (0)

Anonymous Coward | more than 4 years ago | (#30013630)

68 feet per second = 46.4 mph

Re:Standard Calculus (1)

realityimpaired (1668397) | more than 4 years ago | (#30013768)

You've almost made exactly the point I was going to make... the way a GPS calculates your average speed is by measuring the distance travelled between pings and calculating an average speed, assuming that your velocity was constant between the two points.

The first of the two pings is at a stop, presumably at a traffic light waiting for it to turn green.

The critical condition that you're missing in your calculation is that there's no way of knowing how long after that first ping the traffic light actually turned from red to green. That is, at what point he started accelerating, and for how long he was accelerating to travel 2040 feet. Practically speaking, though, there's just no way to fudge the numbers to support the contention that he was only travelling 45mph... the longer it took between the first ping and the light turning green, the worse it looks for his case. Even assuming that he had the full 30s to accelerate, it's looking like the cop decided to try to cut him a break and wrote the ticket for less than he was actually clocked at.... I'm pretty sure that most of us have, at some point, been let off with a warning in lieu of an actual ticket.

Re:Standard Calculus (1)

sjames (1099) | more than 4 years ago | (#30013888)

Rough calculations suggest at most 52 MPH. That's assuming that from stopped, he accelerated to his max speed in about 6 seconds, then decelerated to 45 in time for the last 1 second interval.

While that is over the speed limit, it's significantly less than 62 MPH.

Re:Standard Calculus (0)

Anonymous Coward | more than 4 years ago | (#30013844)

This is a fine example of the lack of Math skills. You calculated fps. not mph.

Re:Standard Calculus (0)

Anonymous Coward | more than 4 years ago | (#30013746)

It's not really a problem because the distances are well-known -- they're on the map, and they know where the radar readings were taken for comparison. The math then becomes simple, and you can easily apply an uncertainty level to everything to determine whether the story is plausible or not. At the time of the first articles about the case there were some articles that provided a map (the father was holding it up in one of the newspaper shots), including the positions of the widely-spaced GPS coordinates. I'll see if I can find it.

Let's face it -- 30 second pings allows for a lot of variation in speed (slower and/or faster) to yield the same average speed.

Re:Standard Calculus (1)

kdemetter (965669) | more than 4 years ago | (#30013382)

What i find strange is that there is only an average recorded speed. My gps can tell me my speed at the exact moment, so if i would record that , it would show my speed , exactly over time . Then you would also be able to see where i stopped , and when exactly when i speeded. So it would be much more acurate then a radar.

So , bad GPS tracking system.

Re:Standard Calculus (5, Informative)

tokul (682258) | more than 4 years ago | (#30013406)

My gps can tell me my speed at the exact moment

No, it does not. GPS only tells you your average speed between two GPS pings. Ping 1 - you are at X, ping 2 - you are at Y, your current speed is how fast you must move in order to get from X to Y in time between ping1 and ping2.

Re:Standard Calculus (2, Informative)

kdemetter (965669) | more than 4 years ago | (#30013452)

yes , well , then these pings are very close together , because it near exactly matches the speed my car is going .
Offcourse , it may be off by some , but the same is true for the radar.

If i went 62mph , at a given time , i would be able to see that on my gps . It won't show as 45mph.

Re:Standard Calculus (1)

Sique (173459) | more than 4 years ago | (#30013474)

I have often the GPS showing me my current speed, and I also have a digital speedometer. I guess that the intervals for updating the current speed are about one second at the speedometer and about 10 seconds at the GPS.

Re:Standard Calculus (1)

bickerdyke (670000) | more than 4 years ago | (#30013840)

yes. but when you want to STORE the GPS-data for quite a long while, you'd reduce the recording interval

Re:Standard Calculus (2, Informative)

raynet (51803) | more than 4 years ago | (#30013494)

Actually that depends on the GPS. Mine updates the speed and heading information every second but stores the information only every 15 seconds. So each saved record contains the average speed for the past second, not the average speed of the 15 second interval.

It uses Doppler shift (5, Informative)

Alef (605149) | more than 4 years ago | (#30013692)

A GPS typically calculates velocity from Doppler shift of the D-band signal. This give higher accuracy since the position reading is somewhat unreliable. It also means you can (in principle) get the velocity information virtually instantaneously without having to sample two locations. However, in reality a lot of averaging and filtering is going on, and I think many receivers weighs in both position deltas and Doppler shift in the equations, so the reading is going to have at least some lag.

(Reference [aprs.net] )

Re:Standard Calculus (1)

notarockstar1979 (1521239) | more than 4 years ago | (#30013490)

Re:Standard Calculus (1)

kdemetter (965669) | more than 4 years ago | (#30013552)

Well , neither can the radar.

Re:Standard Calculus (1)

elnyka (803306) | more than 4 years ago | (#30013822)

What i find strange is that there is only an average recorded speed. My gps can tell me my speed at the exact moment, so if i would record that , it would show my speed , exactly over time . Then you would also be able to see where i stopped , and when exactly when i speeded. So it would be much more acurate then a radar.

So , bad GPS tracking system.

No, it can't. Law of physics dude, not unless you have a GPS based on 'funny action at a distance' quantum mechanics star-trek hocus pocus.

Re:Standard Calculus (4, Insightful)

tg123 (1409503) | more than 4 years ago | (#30013652)

If the average speed is 45 mph, and he was stopped at the end (ie speed 0), then at some point he was going above 45. Especially since you can't stop instantaneously. This is like calculus you learn in High School... If the Judge ruled the other way, the future of America would be even in deeper sh*t than it already is.

Wondering where you got average speed from ?

If you had followed the first link http://tech.slashdot.org/story/08/07/18/0318228/GPS-Tracking-Device-Beats-Radar-Gun-in-Court [slashdot.org] (a bit of effort I know 2 clicks with the mouse) you would have come to the article
http://hothardware.com/News/Speeding_Radar_Gun_vs_GPS/ [hothardware.com]
with the quote :-

..... Rocky Mountain Tracking device was "very" accurate, to within a couple of meters on location and to within 1 mph on speed. Dr. Heppe also pointed out that the GPS device released instantaneous data, and not data averaged over a distance.

I personally think this article ( http://www.pressdemocrat.com/article/20091104/ARTICLES/911049901/1334/NEWS?tc=autorefresh [pressdemocrat.com] ) does not have enough info to make any meaningful decisions from.

Re:Standard Calculus (4, Informative)

msauve (701917) | more than 4 years ago | (#30013788)

Wondering where you got average speed from ?

Average speed is easily calculated, based on the statement from this article [pressdemocrat.com] :

"It recorded Malone sitting at a stoplight at Frates Road and 30 seconds later going 45 mph 2,040 feet farther down the road,"

That would be 2040 ft / 30 sec === 0.386 mi / 0.0833 hr = 46.4 MPH

I personally think this article does not have enough info to make any meaningful decisions from.

No, but it does provide "related links" to other articles which do provide sufficient detail. He started at 0 MPH, ended at 45 MPH, and averaged 46.4 MPH. That can't be done without exceeding the speed limit of 45 MPH.

Political Calculus (-1, Flamebait)

Anonymous Coward | more than 4 years ago | (#30013670)

Barack Obama regarding the Ft. Hood massacre:

"Barack Obama cautioned a stunned public on Friday against drawing quick conclusions on a shooting rampage by an officer at a Texas military base that killed 13 people.

The president made the comments as the commander of Fort Hood, the US’s largest base for deployments to Iraq and Afghanistan, quoted witnesses as saying the suspected gunman, Major Nidal Malik Hasan, shouted the Muslim declaration “Allahu Akbar” – God is great – as he opened fire. Speaking at the White House, Mr Obama said: “We don’t know all the answers yet, and I would caution against jumping to conclusions until we have all the facts.”"

Barack Obama regarding Skip Gates v. Cambridge police:

""Now, I don't know, not having been there, and not seeing all the facts, what role race played in this," Mr Obama told a prime-time press conference, when asked about his reaction to the highly-publicised incident.

"But, I think it's fair to say, number one, any of us would be pretty angry. Number two, that the Cambridge police acted stupidly in arresting somebody when there was already proof that they were in their own home.""

I guess it's only fair to jump to conclusions if the alleged perpetrator is a white, non-muslim. Way to go, you fucking hypocrite.

Re:Standard Calculus (2, Informative)

natehoy (1608657) | more than 4 years ago | (#30013804)

Most of these tracking units are calculating speed in "near real time" based on GPS readings every second or so, and are pretty accurate. The ones that TRACK your speed, like the one the kid had, send the current speed and position in a "ping" every 30 seconds.

So, in all likelihood, the data was accurate for the time it was sent - it wasn't an average over 30 seconds, it was a snapshot of an accurate speed every 30 seconds.

However, this proves nothing, since he was at zero at the light, 45 a half minute later, then got flagged for speeding at neither of those times. He could have been mashing the pedal from the stoplight and been on his way to 62 when the snapshot read 45.

More telling would have been the logs from his driving in general.

Sounds like california (0)

EnigmaticSource (649695) | more than 4 years ago | (#30013294)

Last time I beat a speeding ticket in that state... I paid for it dearly. Six tickets for less than 3 mph over the limit in a month. I find, although morally repugnant, it's much cheaper to pay up now and complain later; rather than to invert the order.

Re:Sounds like california (1)

EnigmaticSource (649695) | more than 4 years ago | (#30013316)

Just to clarify, I was in a small town (Atwater). It's the kind of place where everyone knows your name (and in a biblical sense, probably your cousin). Elsewhere YMMV.

Re:Sounds like california (4, Insightful)

91degrees (207121) | more than 4 years ago | (#30013340)

Have you considered driving 3mph slower? It seems that they really mean it when they post the speed limits in your area.

Re:Sounds like california (0)

Anonymous Coward | more than 4 years ago | (#30013356)

In a 50 MPH zone, ~3 is within the margin of error. California CHP guidelines state that they should not issue a ticket for anything less than 10% over the limit.

Re:Sounds like california (4, Informative)

MichaelSmith (789609) | more than 4 years ago | (#30013384)

The margin of error is for your speedometer, not for you to knowingly drive over the limit.

(tolerance is 3% here in Victoria, Australia);

Re:Sounds like california (1)

TangoMargarine (1617195) | more than 4 years ago | (#30013428)

If his speedometer had a flaw that affected it by 10%, the speed would appear to be legit each time. Of course, there's the matter that he would know the gauge was faulty after the first ticket...

Re:Sounds like california (2, Informative)

bickerdyke (670000) | more than 4 years ago | (#30013860)

The error margins of speedometers (at least here) have to be calibratet to err on the safe side. It may show 10%+4km/h faster than your actual speed, but never ever slower.

http://en.wikipedia.org/wiki/Speedometer#International_agreements [wikipedia.org]

Re:Sounds like california (1)

91degrees (207121) | more than 4 years ago | (#30013386)

Yes, but those are guidelines. Clearly law enforcement don't pay attention to them. Whether they should or not they are perfectly legally entitled to ticket you for going at that speed. Seems to me that after not learning the first 5 times, you only have yourself to blame the 6th.

Who cares what they should or shouldn't do? It's what they do that matters. Relying on expected behaviour that based on experimental results doesn't happen suggests a disregard for reality.

Re:Sounds like california (0)

Anonymous Coward | more than 4 years ago | (#30013400)

The guidelines are how I beat the first ticket, second, third, and fourth... Then I gave up and just started paying them. A days work is less than a petty ticket; They knew it and I as well... that perhaps is the problem.

And just for reference, according to my speedometer, I was doing the limit, and I had had it calibrated.

Re:Sounds like california (0)

Anonymous Coward | more than 4 years ago | (#30013456)

... a days work is more than a petty ticket.

That'll teach my to rant drunk.

Re:Sounds like california (4, Insightful)

shentino (1139071) | more than 4 years ago | (#30013680)

I think there should be an offense known as "frivolous citation"

A cop knowingly writing a bogus ticket should get a huge fine of their own.

Too bad the cities that rely on ticket revenue won't bite.

Re:Sounds like california (1)

91degrees (207121) | more than 4 years ago | (#30013780)

Well, that's irritating.

Although my point still stands. Drive just below the speed limit. The fact that you happen to be in the right isn't going to stop you getting a ticket.

Re:Sounds like california (1)

WindBourne (631190) | more than 4 years ago | (#30013858)

What? You get tickets for doing 3 over a limit? Give me a break. The ONLY way that a cop is going to do that is if they are targeting you, or if it is in a school zone (and I doubt even that). Nearly all states give you 5 to 10 over (colorado gives 10; Seattle and portland gave 10; Atlanta gave 15-20 depending on where you were driving; San Jose gave 10).

Radar takes an average vs GPS point (0)

AGMW (594303) | more than 4 years ago | (#30013296)

The "average" nature of radar does offer a potentially dangerous way to _not_ get caught: A friend was pressing on and came over the brow of a hill to see a Police officer pointing a radar gun at him. He KNEW there was nothing behind him and stamped on the breaks resulting in him stopping sufficiently quickly that the radar gun hadn't posted a speed before he stopped - adding sufficient "zero speed" into the average calculation meant he wasn't caught speeding. He then calmly, and slowly, drove into the lay-by because he assumed, correctly, that the officer would probably want a quiet word.

Re:Radar takes an average vs GPS point (0)

Anonymous Coward | more than 4 years ago | (#30013390)

You can do that, but then you could also get nailed with careless or wreckless driving....

Re:Radar takes an average vs GPS point (5, Funny)

Anonymous Coward | more than 4 years ago | (#30013436)

You can do that, but then you could also get nailed with careless or wreckless driving....

Wreckless driving usually gets you in less trouble than the alternative...

Reckless. </pedant>

Re:Radar takes an average vs GPS point (1)

AGMW (594303) | more than 4 years ago | (#30013550)

Not sure you could be done for careless driving as you have shown your above average observation skills by seeing the speed trap in time to do something about it.
I also pointed out that he knew there was nothing behind him and so he knew he wasn't going to be causing any danger to anyone behind him - he stopped and moved on pretty quickly and it was a two lane road and he was in the inside (AKA "slow").

That all said, I take your point, indeed I pointed it out myself by saying "potentially dangerous". hmm ... does that make it my point?

Re:Radar takes an average vs GPS point (1)

Paradise Pete (33184) | more than 4 years ago | (#30013658)

you could also get nailed with careless or wreckless driving....

Isn't wreckless driving one of the usual goals?

30 seconds is a low sample rate (2, Informative)

SlashSim (229766) | more than 4 years ago | (#30013308)

I expect sampling as close to continually as possible would make for a tighter defense, 30 seconds is pretty coarse to predict a spot speed.

Amazing (1)

zoomshorts (137587) | more than 4 years ago | (#30013346)

" At issue was the distance from the stoplight -- site of the first GPS 'ping' that showed Malone stopped -- to the second ping 30 seconds later, when he was going 45 mph." No matter what, a car that goes from 0 to 45 in 30 seconds is crawling. Gimme one, I am that old fart in front of you in the fast lane:P

Re:Amazing (1)

91degrees (207121) | more than 4 years ago | (#30013358)

The average speed was 45mph. This means he went to 90mph in those 30 seconds.

Re:Amazing (1, Informative)

Anonymous Coward | more than 4 years ago | (#30013414)

no it doesn't. IF it's an average over 30 seconds (which seems a stupid way to record data, and VERY unlikely to exactly match the speed limit the way it has), ALL it means he travelled .375 miles in those 30 seconds. He could do this by averaging 90 over 15 seconds and remaining stopped for 15 seconds, or accelerating to above 45 mph (since he was stopped [for at least 30 seconds if these are averages] at the beginning of this run).

Basically, we don't have all the data necessary. I have to assume the people arguing the case did, as there's no way to know. Like another poster said: we don't know how far he got from that stoplight in 30 seconds and what portion of the 30 seconds he was just stopped at the stoplight still.

Re:Amazing (0)

Anonymous Coward | more than 4 years ago | (#30013426)

Not necessarily. He could've accelerated to 50-55mph in 5-10 seconds, cruised to get his average up to 45, then slowed to 45 by the time of the reading. IMO, the radar data is inconclusive - it shows he was going above 45mph for at least part of the trip, but it's also possible that he never exceeded 55 or so, even allowing for gradual acceleration.

Re:Amazing (1)

Paradise Pete (33184) | more than 4 years ago | (#30013638)

The average speed was 45mph. This means he went to 90mph in those 30 seconds.

I'll bet you never did well on brain teasers. Here's one for you - if on a two-mile journey you go at a speed of 30MPH for the first mile, how fast do you have to go in the second mile to average 60MPH for the trip?

Radar Guns... (3, Insightful)

Manip (656104) | more than 4 years ago | (#30013360)

Radar Guns aren't completely accurate all of the time. But a 40% increase is far beyond what you might expect from an incurrently calibrated radar guns. The only realistic alternative is hitting a car travelling in the other direction but since police are trained to only use a radar gun on a straight road and at a certain angle that might be unlikely too.

So in this case I would side with the police. Unless they're just flat out lying which I cannot discount.

Re:Radar Guns... (1)

X0563511 (793323) | more than 4 years ago | (#30013502)

Doesn't the angle of the reading effect it as well? How do they deal with that? (or is the effect of this so small as to be insignificant? As well for slopes, it seems like the gun measures a 2d vector, completely ignoring the third vector of the car's motion.

Re:Radar Guns... (0)

Anonymous Coward | more than 4 years ago | (#30013684)

police are supposed to shoot mostly straight on.
Anything else actually will give you a break as your velocity towards the officer would be less.

Re:Radar Guns... (1)

Der PC (1026194) | more than 4 years ago | (#30013634)

We had a case up here of a police officer shooting a plane behind the car, and then claiming that the car was travelling almost 400KM/h.

As it looks to me, that judgement is in effect creating a blanket permission to officers to "make up" speeding tickets without having the tickets challenged.

Heavily stupid sentence.

Re:Radar Guns... (0)

Anonymous Coward | more than 4 years ago | (#30013738)

Agreed. I was in the slow lane going about 85, the person I was just about to pass was in the fast lane going about 65 (the posted limit). When we saw the cop, he put on his breaks and I kept rolling along. Police pulled out of the median and gave chase and pulled him over, not me. I assume he got a ticket for going close to 85. Good for me, bad for him.

Re:Radar Guns... (0)

Anonymous Coward | more than 4 years ago | (#30013716)

So basically you're saying the police is right unless they are not.
Here you go, +4 insightful.

Sgt is an idiot (5, Insightful)

syousef (465911) | more than 4 years ago | (#30013422)

'This case ensures that other law enforcement agencies throughout the state aren't going to have to fight a case like this where GPS is used to cast doubt on radar,' said Sgt. Ken Savano,

Well if the summary is true (and I know it might not be), it actually means the opposite since the GPS data was considered at the trial. That means others may try to present their GPS data in future. It certainly doesn't mean that people can't try that defense. There was no precedent set that the GPS data was less reliable than the radar. It's just that the GPS data could be interpretted to be in agreement with the radar data. Also, this is only applicable to one kind of GPS unit under one very limited set of circumstances.

In other words Sgt. Ken Savano is either misrepresenting the whole situation or is incompetent when it comes to the prosecution of speeding violations. Either way he's coming across as dim witted and it raises serious doubts for me about his ability to perform his duties as a police officer, since he can't seem to understand the law.

Re:Sgt is an idiot (5, Interesting)

black3d (1648913) | more than 4 years ago | (#30013464)

The judge who allowed the case to proceed in the first place is also an idiot. I see no good reason why the case wasn't thrown out immediately.

I can't quite fathom why the court system allowed "So what if the radar said I was going 62 at that point in time. I was going at 45 at two other completely different points in time." as an argument.

I can see how it happened though -
1. Stupid, dishonest, ignorant kid goes home and tells his parents "No, I wasn't speeding".
2. Parents get GPS data readout which shows he was going at 45 "around that time" in two different readings.
3. Parents lack basic knowledge of trigonometry and can't translate the speed over the distance travelled between readings.
4. Neither can the court. Case proceeds.

Seriously though, in every case like this where the defendant (the kid) lies to the court, they should be charged with contempt. If you don't want to lie, take the 5th. It sickens me daily that the majority of our courts time is wasted with dickless wonders who are too scared to accept responsibility for their actions.

Re:Sgt is an idiot (5, Insightful)

Anonymous Coward | more than 4 years ago | (#30013482)

I fail to see how this has anything to do with trigonometry.

Re:Sgt is an idiot (1)

tangent3 (449222) | more than 4 years ago | (#30013856)

I think he meant Calculus..

Re:Sgt is an idiot (0)

Anonymous Coward | more than 4 years ago | (#30013522)

He was "certainly" not driving fast...
He is "just" a fan of fast driving: "Malone was on his way to Infineon Raceway when ..." :-)

Re:Sgt is an idiot (2, Insightful)

black3d (1648913) | more than 4 years ago | (#30013554)

On further thought, I understand why the judge allowed the case to proceed. In normal circumstances, where it is "cop's word vs perp's word", the cop's authority is sufficient to validate the radar reading. However, as soon as *anything* else is introduced to counter, it becomes (as in this case) "cop's word vs perp & gps". So now you've got to proceed to case to prove that the GPS doesn't disagree with the cop.

Still don't like the kid tho. ;)

Re:Sgt is an idiot (1)

pieisgood (841871) | more than 4 years ago | (#30013574)

ah but don't you need calculus to prove the average velocity over time which is what essentially is used to find him guilty?

Re:Sgt is an idiot (1)

black3d (1648913) | more than 4 years ago | (#30013604)

Bah! Trigonometry.. Calculus.. same thing. They both involve numbers, amirite?

Disclaimer: The ahove statement is not serious. It's 5am here and I've just finished my fourth redbull. I think I need to sleep.

Re:Sgt is an idiot (2, Insightful)

jonbryce (703250) | more than 4 years ago | (#30013644)

The reason is that you need to hear that evidence before you can come to those conclusions.

Re:Sgt is an idiot (1)

shentino (1139071) | more than 4 years ago | (#30013686)

That would be perjury, not contempt.

Re:Sgt is an idiot (1)

selven (1556643) | more than 4 years ago | (#30013748)

I'm pretty sure that denying that you committed a crime, even if you did commit it, is not perjury or contempt of anything. Otherwise, everyone who pleads not guilty but is found guilty would be in very big trouble.

Re:Sgt is an idiot (1)

noidentity (188756) | more than 4 years ago | (#30013744)

Correct me if I'm wrong, but GPS doesn't ever report (instantaneous) speed, just location (insert Heisenberg joke here). Given the times of locations, you can calculate average speed. If I travel 60 miles in one hour, I could have gone 60 MPH the whole way, or 100 MPH and then waited at the destination for the remaining 24 minutes. In both cases my average speed would be 60 MPH. I suppose if the GPS locations and times showed that I traveled 60 miles in 30 minutes, resulting in 120 MPH average speed, there's no way I could have covered that distance without going at least 120 MPH for part of it. But maybe I had my car carried in an airplane or something...

Re:Sgt is an idiot (0)

Anonymous Coward | more than 4 years ago | (#30013764)

So what would you do to the prosecutor and police that framed two defendants for murder? The case that is before SCOTUS where two people spent about 25 years behind bars for something they didn't commit.

Re:Sgt is an idiot (1)

1s44c (552956) | more than 4 years ago | (#30013562)

...he's coming across as dim witted and it raises serious doubts for me about his ability to perform his duties as a police officer, since he can't seem to understand the law.

What a shame this kid wasn't stopped by one of the vast majority of smart, intelligent, helpful, and caring police officers instead of an ignorant bully boy with a chip on his shoulder.

I'm being sarcastic.

Re:Sgt is an idiot (1)

divisionbyzero (300681) | more than 4 years ago | (#30013814)

++

i just got off the toilet (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#30013424)

i shit out an obama.

PLOP!

The path travelled (1, Informative)

Anonymous Coward | more than 4 years ago | (#30013458)

Since the article didn't give enough information (and manages to misspell one of the street names), I googled around and figured out the path taken (from http://www.pressdemocrat.com/article/20071002/NEWS/710020308?Title=Case-pits-police-radar-against-GPS-in-teen-s-car# [pressdemocrat.com] ): http://maps.google.com/maps/ms?hl=en&gl=us&ie=UTF8&oe=UTF8&msa=0&msid=105238595049957684644.000477c5e46e20fe9dff3&ll=38.2325,-122.591393&spn=0.010956,0.010257&z=16 [google.com]

The first point is when he was stopped at the intersection, the middle is (probably) where the cop got him on radar, and the end is where the GPS clocked him at 45 MPH.

I estimate that's about 2.2k feet from a dead stop in 30 seconds, which puts his average speed at 50. It's pretty much a given he was speeding when the cop radar'd him and he put on the braked.

Average? Or last sample? (1)

gwdoiron (1590237) | more than 4 years ago | (#30013486)

From TFA, the pings noted were actually 30 seconds apart.
My last GPS reported speeds every second.
So, the question is, what was the ping rate of the GPS on the car? Was the logged value the average of the past 30 seconds of pings, or just the most recent ping?
(Yes, in all likelyhood, it's an average of values, the kid was speeding, and figured that if he didn't go over 75 and trigger the auto-phone-home-warning, his parents wouldn't find out.)

Re:Average? Or last sample? (0)

Anonymous Coward | more than 4 years ago | (#30013548)

The data is

T=0, V=0, D=0
T=30 V=??
T=[0..30] = 62 (from Radar gun)
D(30) = 2040 ft
V(ave, 0..30) = 45 mph (gps)

According to various web sites, his car can go 0..60 mph in 6-8 seconds. If we take the fastest (6), and the maximum speed he could travel before getting a ticket (45+10%=49.5, call it 50), it will take 5 seconds to accelerate to 50mph, and he could then travel for 25 seconds at 50mph. Unfortunately, he would then only be 2016ft down the road. He must then have gone above 50mph (at least 54), meaning he should get a ticket. As far as I can see, any other scenario means he will have gone even faster at some point (and braked hard).

Forget the math, you're missing the point here... (1)

geekmux (1040042) | more than 4 years ago | (#30013500)

This ruling establishes case law from here forward. Her ruling was in favor of the Police and their technology. Lawyers from here forward will stand a snowballs chance in hell of appealing, even if the GPS data is right and the radar gun is wrong. THAT was the point of this ruling, and unfortunately, it smacks of corruption.

Criminal, you might still stand a chance in proving your innocence these days. Civil? You might as well bend over now. Pisses me off.

Re:Forget the math, you're missing the point here. (3, Insightful)

4D6963 (933028) | more than 4 years ago | (#30013640)

No, and allow me to dismiss this as some anti-The Man banter. Radars are standardised, calibrated, designed for the purpose, operated in proper condition by trained operators, etc... The log from someone's GPS is made by the software from some company which won't necessarily disclose how it gathers, processes and stores its data, furthermore those can be imprecise (how many times does your GPS show you as crossing through buildings when you're driving in city centers?), and who's to say that no one tampered with the data (in this case, edit the data in the log to make it seem impossible to have speeded).

So the decision is only common sense. If you really need an analogy, that's as if you provided a court with a written transcript of conversation when they have an audio recording done with their own equipment of the same conversation.

Re:Forget the math, you're missing the point here. (1)

GravityStar (1209738) | more than 4 years ago | (#30013706)

... operated in proper condition by trained operators, etc...

I suggest that this is not the proper usage for a police force.

Re:Forget the math, you're missing the point here. (1)

cronot (530669) | more than 4 years ago | (#30013862)

Please mod the parent up to the moon. I've been reading all the comments on the story, and it baffled me that no one caught this simple fact - GPS logs can be easily tampered with, or even forged. I don't know if the ruling on this case was made with this technical knowledge, but it's nevertheless a good thing a bad precedent wasn't set. Nevermind GPS accuracy, GPS logs just aren't a reliable source of evidence in the first place.

Re:Forget the math, you're missing the point here. (1)

rat7307 (218353) | more than 4 years ago | (#30013898)

Agreed,

There is no real data integrity with these devices.

I can get the track log of my GPS, manipulate the data and then shove it back in to the device...

Any good lawyer could get this 'evidence' thrown out.

There's been cases here in Australia where the GPS evidence WAS allowed and they got off the infringment, but I can only assume that the prosecuting lawyers were incompetent and did not pursue the possibility of bad data in the GPS.

Also, the Radar is a certified calibrated instrument,and the GPSr is not. Although accurate, there is always a variable amount of uncertainty in every reading (up to 10-15 meters per sample in a moving vehicle) and in a majority of GPSrs this uncertainty is not stored in the logs. Radar wins again on that front.

As for the logs, most GPSrs I use store the last speed value at the log interval, not an averaged speed between then and the last stored sample, so it is safe to assume at X time on the log the car was going Y speed, but for the 10 seconds in between it could have been going anything between 0 and lightspeed. (presuming it is storing every 10 seconds.....)

Traffic court... (0)

7-Vodka (195504) | more than 4 years ago | (#30013632)

Are you serious? The article is treating traffic court to some kind of regular court standards... Traffic court is a fucking kangaroo court with dubious legality and no oversight.
Everything about it stinks to high heaven from the magistrate who is supposed to be unbiased but is really trying to con you to the judge who acts as judge, jury and prosecutor.

The judicial system is only supposed to adjudicate over a matter when one party can show damages caused by another. I'm sure this is not the case for silly traffic tickets.

I wish some lawyer who is familiar with how the real court system works would chime in and list all of the differences here.

I have witnessed many times people making illogical arguments and fining drivers when clearly under any type of innocent until proven guilty system the drivers should have gone free.

Traffic court systems are chaotic, disorderly and inconsistent cesspools of nonsensical arguments and big egos...

There is only one way to describe the whole traffic court system: unconstitutional.
The only reason it remains is because of the sheer massive size of the monstrosity, how much income and how many jobs depend on the entire thing.

Re:Traffic court... (1)

bmr91 (1653939) | more than 4 years ago | (#30013700)

I WOULD support you argument, but I'd rather not have my liver all over the the hood of a van

Re:Traffic court... (1)

selven (1556643) | more than 4 years ago | (#30013752)

Running over people is illegal regardless of traffic laws, and will be handled in a normal criminal court.

Re:Traffic court... (1)

bmr91 (1653939) | more than 4 years ago | (#30013800)

I would also rather not have my "death by van" be handled in any kind of court. Having some guy pay a speeding ticket instead of me dying sounds like a much better option

Re:Traffic court... (1)

mikelieman (35628) | more than 4 years ago | (#30013808)

The only reason it remains is because of the sheer massive size of the monstrosity, how much income and how many jobs depend on the entire thing.

That -- and the little fact that you agreed to these crazy rules when you signed that driver's license application and vehicle registration application. Caveat Emptor applies to transactions with the State, too. But hey, the value of a good set of Papers is without measure, so it's generally worth the extra hassle.

GPS speed not accurate 100% of the time (2, Interesting)

Amadodd (620353) | more than 4 years ago | (#30013666)

How the court can even consider comparing stationary technology that operates up to a few hundred meters with something that is 20,000 kilometers away traveling at 14,000 km/h is beyond me. GPS accuracy is effected by builings, mountains, etc.

Re:GPS speed not accurate 100% of the time (1, Insightful)

Anonymous Coward | more than 4 years ago | (#30013698)

So a kid with a flashlight and a broken wristwatch told to switch on the light at 8:00 AM is more accurate than our predictions for the sunrise on a given day and longitude/latitude?

Re:GPS speed not accurate 100% of the time (1)

selven (1556643) | more than 4 years ago | (#30013766)

How the court can even consider comparing stationary technology with something that is 149,600,000 kilometres away that is travelling at a relative speed of 107,000 km/h is beyond me.

Re:GPS speed not accurate 100% of the time (1)

bmr91 (1653939) | more than 4 years ago | (#30013776)

Yet we can still beam HDTV to thousands of people at the same distance but if somebody stands in front of the TV my remote doesn't work.

The question is not the accuracy of GPS, it's the fact that the car's speed was only recorded at 30 seconds intervals, and anything could have gone on in between those intervals as long as it brought his average speed to 45 mile/hr.

I calculate a peak speed of between 68-70 mph (1)

sitech (1673392) | more than 4 years ago | (#30013756)

So assuming he gunned it as hard as he could and he accelerated and decelerated linearly, I estimate his max speed to be between 68 to 70 mph over a period of 8.83 seconds. That is at the max acceleration he can achieve that would fit the data (60 mph in 7.74 seconds). Any other peak speed would require slower acceleration (its like a parabola). He could have accelerated faster than that, but 7.74 seconds is reasonable for an average car.

Re:I calculate a peak speed of between 68-70 mph (1)

sitech (1673392) | more than 4 years ago | (#30013778)

So assuming he gunned it as hard as he could and he accelerated and decelerated linearly, I estimate his max speed to be between 68 to 70 mph over a period of 8.83 seconds. That is at the max acceleration he can achieve that would fit the data (60 mph in 7.74 seconds). Any other peak speed would require slower acceleration (its like a parabola). He could have accelerated faster than that, but 7.74 seconds is reasonable for an average car.

Sorry, typo. He can't accelerate faster than 60 mph in 7.74 seconds and match the data. He can however accelerate slower.

what's wrong with America (4, Insightful)

elnyka (803306) | more than 4 years ago | (#30013838)

Fuck the parents and fuck the kid. A good parent would have told the kid "tough luck, we pay the ticket and you pay us back from your allowance". But noooooooooooo, better to make a fucking mountain out of a grain of sand at taxpayers' expense to prove a point that is questionable to anyone with a basic understanding of calculus and physics.
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