[Bobcat]

I`ve been told that police radar picks out the strongest signal ... not always the closest object . For example , if a semi was 50 yards behind you , the unit would read the trucks speed and not your car`s . If I understand radar correctly , it cannot specify which vehicle is speeding ( laser can ) ... unless you are the only car on the road . For that reason , if you are the lead vehicle , you are screwed . From what you say , he probably wasn`t paying attention and looked up when the alert on the unit went off and saw you after the truck passed . I had a friend who was a GA trooper and he said they relied on the unit alerting them when a vehicle was over the trigger point ... then it was up to him to figure which vehicle it was .
Don`t know how it is in Canada , but the police have to be able to prove the unit is properly registered and calibrated before each shift . If not , the ticket can usually be fought successfully . You might try Valentine`s and Cincinnati Microwave`s ( radar detectors ) web sites for more info .
Good luck .