Thanks for the advice Kadrien! I already did ask in writing for the calibration records for the day of the infraction but they just sent me a record of SMDs that were tested within the last 2 years as they say they only need to be certified every 2 years.
I kind of figured they could sit on private property but I wasn't sure. But do you think having his location as on the shoulder when there is no shoulder and he would have had to have been in a parking lot would be enough of a technicality to get the ticket dismissed?
Again, thanks so much for your help!

