From: whs70@dancer.cc.bellcore.com (sohl,william h)
Subject: Re: LIDAR demo on Discovery Channel
Organization: Bellcore, Livingston, NJ
Date: Thu, 12 Nov 92 16:34:40 GMT

In article <1992Nov12.030343.2658@pony.Ingres.COM> kevinq@Ingres.COM (Kevin Quinn) writes:
>In article <1992Nov11.234548.12945@news.columbia.edu> scs8@cunixb.cc.columbia.edu (Sebastian C Sears) writes:
>>In article <1992Nov11.200930.22847@porthos.cc.bellcore.com> whs70@dancer.uucp (22501-sohl) writes:
>>
>>>Q2 - If braking hard, how does the cop even know it if he doesn't get
>>>a "fix" and therefore some reading which indicates a rapidly 
>>>decreasing speed indicative of hard braking?  LIDAR needs to be
>>>exactly on the car, if it isn't there's no reading that
>>>reflects a changing (decreasing) speed.
>>
>>	Watch the nose dive. Cops don't need no stinkin' radar reading in
>>	a lot of states. They just get believed.

If the only evidence of the speeding charge is the cops observation of
the car "nosediving" I'd expect anyone with a reasonable effort should
be able to have that charge dismissed and/or found not quilty.  There
has to be more evidence than just the fact that a a driver applied his
brakes to sustain a guilty conviction for speedin (exceeding a certain
posted limit).  If (I think it was Vermont that this supposedly
happened in) the speed limit was 55 or 65, how does the cop know
what speed the vehicle was going at when the brakes were applied.
Guilt by assuming that the driver wouldn't have hit his brakes unless
he was speeding is not (IMHO) sufficent to sustain a conviction.
Likewise, I have never seen anyone convicted of speeding without
some actual speed identified on the traffic ticket.  Now I'm
not saying someone might not have had this happen to them, what I am
saying is that I think I'd be able to get the charge dismissed  or found
not guilty because the state has not proven it's case beyond a reasonable
doubt.

>Also - most - or at least _many_ vehicle mounted radar systems have a audio 
>feed of the dopler signal.  You *hear* the vehicle hit the brakes...

No argument, but the original discussion cenetered on LIDAR, not
RADAR.  I'll assume there's no audible associated with LIDAR.  Even
given the audible, that alone should would not be proof that the
vehicle was speeding, it just shows the vehicle was slowing down.
A speeding conviction still requires (IMHO) an actual speed reading.

Of course, everything I've said assumes the cop telling the truth.
If the cop fills in any of the blanks by lieing or just claiming
you were speeding at XXmph, there's not much you can do.  I'm just
saying that absent certain key elements, there should not be a case
against a driver who is observed braking.

Standard Disclaimer- Any opinions, etc. are mine and NOT my employer's.
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