Police cars with onboard cameras

Man of Honour
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17 Oct 2002
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Right.

I was under the impression that a police car, unmarked or otherwise, cannot get an accurate reading of your speed with which to take action against you if you are driving towards them and they are driving the other way - ie, they have not set up a speed trap etc.

It was this assumption that led me to a run in with a fine officer from the New South Wales Police Department. He was coming towards me, but despite this, was able to get an exact reading of my speed.

Can they/do they do that here in the UK?
 
I guess it's hard, but not technically impossible. I assume that the police car would have to maintain a constant speed in order to get an accurate reading?
 
id like to know the answer to this too

to get an accurate reading from a laser / radar speed gun you'd have to be stood still

Obviously if your hurtling towards the vehicle you're taking a read of, at 60 miles an hour, its going to come back to you a lot quicker because you've moved quite a few feet forwards by the time the radar/ laser bounced back

equally even if you could factor in your current speed, to get a reading presentable in court, you'd have to be doing exactly the same speed through the duration, something cruise control wouldnt be capable of

The only way i can think it could be done would be using a distance / time equation using a fixed point similar to vascar system in the UK.

UK however requires they follow you for a significant distance. I was caught using vascar back in 2001 and was followed for 0.75 miles by an unmarked car.

how long did the oncomming copper have sight of you fox ?
 
mobile laser units are able to tell your speed either going away from or going towards them. I don't suppose a car with the correct equipment would be any different.

Oh, also, my office smells funny. :(
 
You could get a reading, I would doubt its accuracy however and I have not read anything about type approved laser devices (or devices otherwise) for use in a moving vehicle.

There is serious doubt about the systems used when following on a timing system never mind coming the other way.

How does a police officer drive and operate/aim accurately a device safely and with consistency?

Probably just baiting you into criminilising yourself.
 
how long did the oncomming copper have sight of you fox ?

About 5 or 6 seconds? He came over a brow of the hill and I had enough time to see the car, say 'Look, thats a nice colour' and then his lights came on and he did a u-turn.

He got my speed spot on - well reasonably, he was 3kmh under my indicated speed at the time. It was as if he could press a button and get an instant reading. How?!

He told me exactly how fast I was going. I admitted it and apologised and he let me off so he wasn't even baiting me into admitting.
 
If you shine something (laser) at the car comming towards you and you know how fast the gap is closing and your speed then i don't see why its so hard to figure out.

Quite a few of my friends didn't think a copper driving towards you could read your speed, but i know as a fact they can.
 
Does he have evidence of your speed? Lasers work by bouncing off your plate and they judge how long it takes to return to the gun, so he would have to have an incredibly smooth ride and quick reactions to have gunned you if you were both travelling towards each other...
 
i guess the issue is that in the UK there is sufficient doubt over these readings that means they cant use them in court

obviously in OZ they can.

Does he have evidence of your speed? Lasers work by bouncing off your plate and they judge how long it takes to return to the gun, so he would have to have an incredibly smooth ride and quick reactions to have gunned you if you were both travelling towards each other...

i think the issue is that the australian courts are willing to accept a reading from a moving vehicle, with the vehicles current speed factored in, something the UK courts wont due to the reasons you've given. Oz are fanatical about speeding, so it comes as no supprise.
 
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Does he have evidence of your speed? Lasers work by bouncing off your plate and they judge how long it takes to return to the gun, so he would have to have an incredibly smooth ride and quick reactions to have gunned you if you were both travelling towards each other...

He said it was all on video, but he didn't show me it or take it any further so I've no idea. He just let me off with a warning.

The point is more... how can they do this and do they do this in the UK. I genuinelly thought it was impossible.
 
The new police cars are said to have new technology which can record the speed of oncoming vehicles, its not difficult if you know the speed of the police car which they will from GPS/calibrated speedo. I think the police cars in America have been using this for a while. A lot of the onboard equipment on UK traffic cars is no longer approved to be used as evidence in court anyway.

A officers "expert" opinion is enough to convict you if they think you are speeding on a motorway this only takes one officer on any other roads it takes two. Any equipment reading or calibrated speedo is used to backup the officers opinion.

You should read the cases on http://forums.pepipoo.com.
 
The time the laser takes to bounce back is absolutely tiny and thus will make only the most minor of differences to the speed reading.
 
Ah, this happened in Oz?

I might be wrong but last I checked there is no devices in the UK to use while coming in the opposite direction that would provide admissible evidence.
 
[TW]Fox;14649570 said:
The point is more... how can they do this and do they do this in the UK. I genuinelly thought it was impossible.

as already said, there are no devices approved for use in the UK in a moving vehicle due to the doubts people have given.

You can get a reading, it just wouldnt ever be used in court so the police dont bother trying.

You've experienced first hand how fanatical the australians are about speeding. We thought it was bad here, at least here most forces have a marked speed camera van. In oz, all mobile cameras are just little cameras on 2 foot high tripods lol.

So they allow the use of readings from a moving car, and factor in the vehicles current speed into the equation, to work out the speed. The fact it wasnt totally accurate, should tell you why it isnt used here. They figure if it says you're doing 20 over the limit, and its only inaccurate to 10km/h then your still speeding. Something the UK courts would never allow.
 
The time the laser takes to bounce back is absolutely tiny and thus will make only the most minor of differences to the speed reading.

It won't make any difference since the equipment will have a built in algorithm based on distance and allow for the return laser time, this will be factored into the end speed calculation.

I was too pulled for doing over the speed limit by a copper comming towards me in a 30, he told me my speed which was as good as 100% bang on since i had the GPS display up at the time.
 
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