VASCAR doesnt have to be checked every shift and a lot of the newer prolaser type handheld stuff is self calibrating too now from what I've seen
Here we go.
Tom, VASCAR does have to be calibrated every shift as the police policy stipulates. As for hand-held lasers, you are correct that they don't need calibrating but then I didn't say they didn't. They have to be placed on tripods as per their manufacturers operating instructions, supported by the ACPO for the following scientific reasons:
"1 degree movement of the operator's hand moves the beam 6-7ft for every 100 yards the beam travels from the gun."
The Prolaser II? Probably one of the worsed examples of inaccurate LIDAR in use and prolific for human error - as is the LTI 20-20. The use of these
clever bits of equipment requires surgical-like training. You need to either: 1, hold them in your hand pointing at a spot on a moving car and MAINTAIN that spot to get a reading; or 2, mount it on a tripod so it reads the movement of a vehicle as it passes a fixed spot. Method 1 produced so many errors (no surprises) that they favoured method 2, nationally. Funny though .... how many speed-guns have you seen being held, and how many on tripods?
Challenge the flimsy attempt of any copper trying to do you with a speed-gun and in 99.9% of cases it'll be dropped unless the documentation of any offence was recorded as it was
legally supposed to be. No court will uphold anything that is unlawful and if demonstrated that a record of an offence was obtained unlawfully (in this instance with most of what I've said here). Equally, presenting this in court, no court will tell you to "oh shut up". A traffic warden not wearing his hat in an attempt to void a parking ticket maybe, but a police officer breaching operational protocol? No!