I am a Captain Paramedic for the Phoenix Fire Dept. In November 2004, I was working on Engine 41 and we were called to the scene of a 962 on I17. It was around noon and there was light to moderate traffic across the 4 lanes of traffic near an off-ramp. E41, as per PFD SOPs, was parked near the accident in a position to divert traffic away from where we were treating patients. As I was evaluating the 2 adult passengers in the front seat and the 2 infant passengers in the rear seat, an officer approached the scene on foot and told us to move the fire truck. I tried to explain several times that we were trying to make the scene safe. He ordered the engineer to move the truck and when he refused, he stated he was going to arrest whomever was responsible if the truck wasn’t moved immediately. I replied that I was responsible for the truck and he proceeded to cuff me. The father of one of the patients had showed up and was pleading with the officer to allow me to finish treating the patients but that didn’t stop the arrest. As he was cuffing me, I gave the radio to the firefighter and told him to call for a Battalion Chief. After the dispatch center asked for the nature of the request for the chief, he replied “they’re arresting my Captain…in fact, you better send a bunch of chiefs”. Interestingly enough, the officers brother is a Phoenix Firefighter. The officer was reported to hove told some family members at an earlier family gathering that if a fireman refused to move a truck, he would arrest him. He was true to his word. The officer also got in the pumper after putting me in the back of his car and moved it off the road. The thing I find most disturbing about this whole ordeal is that a number of DPS officers have been killed or seriously injured at accident scenes very similar to the one we were operating on. We lost a firefighter in a similar manner and that prompted us to change how we place our rigs at accident scenes.