How about actually having a description of the driver/shooter that is even somewhat of a match for the driver of the white van being stopped?? To my way of thinking, THAT constitutes probable cause for the actions shown in this stop--otherwise not.
It is my understanding that this shooter has not let any one get a description of him and they do not have any real idea of what he looks like. If I am wrong, please correct me.
And if the LE does not have a sighting on this shooter- all possibilities should be explored with the white van drivers.
Maybe the tactics are to be "window dressing " to some degree but if they did nothing, all the anti-LE's would have a field day ( as they appear to be having on this thread).