Didn't see a thread for Iowa so I thought I'd post an observation from today.
Driving East on I-80 in Council Bluffs and noticed a vehicle parked on the shoulder with an open trunk. Slowed down and pulled into the left lane and then saw that it was a Deputy Sheriff's car and the officer was standing at the passenger door with what appeared to be a LTI 20/20 shooting at approaching cars.
I have not seen the old open truck bit in awhile. I used to do it with radar pointing to the rear and soon as I got a speeder I would quickly accelerate and the truck would slam shut.