I had a nurse stand behind me for one of my test (Health Clinic). Would not being able to go on the spot make you a 'suspect' for tampering? It was a random U/A and I woke up and used the restroom like everyone else, so when we got test first thing at work I didnt need to go. I sat there in front of them and drank water for about 30-45min. Then when I was ready they followed me in and stand at the door.

Then for another job I was tested at a Hospital and the nurse did not go into the bathroom with me.