just checking the checkpoint... Las Vegas

Ok so there is a DUI checkpoint this Sunday, So Tim and I go down to the location because they have already spray painted the street with their template. They are required by Nevada law post signs 1320 ft. before the checkpoint. And we have been up there ass over this, so we are walking off Sundays roadblock, and get to the 2300 ft. mark and are conversating about the progress, and what the reasons are that they are complying all of the sudden, when we see some kids get Detained by an unmarked car.

So we stop and I pull out my phone, and start to record, After a couple of minuets the Cops asked what we were doing from across the road, we insinuated that we were simply observing, and they went back about their business, but another patrol car came in to the gas station and stayed a few minuets , like they got gas... and then "lights out" pulled behind us, they eventually approached us, and they told us to take our hands out of our pockets, we declined and asked “am I being detained” the lady cop answered no. So our response was, then where does your authority for a lawful order come from. So I got this steroid stud leaning over my shoulder 8 inches from my grill and the old lady cop is shining the flashlight in my eyes. They tried to ask questions, but we did not consent. This went on for more than 30 minuets. We finally just walked off....
David