I'd like to expand on my comments before.
Marshall, I wasn't implying anything when I referenced your comment and I hope you didn't take it that way. I agree completely that JoCo's system doesn't fit with current interop goals or standards. Your statement just reminded me of the incident with the weekend long outage, and JoCo's short sightedness on the matter.
JoCo's TRS was the first trunked radio system I had any experience with. I remember being amazed with features such as officer's having one-on-one encrypted communications between cars (i-call). However, I can tell you that most of the officer's in Kenly (the extreme north end of the county) at the time secretly hated the radio system with a passion. They couldn't reach the south tower, even with the GE in-car radios. They were often plagued with a tone when they keyed up that apparently meant either no channel available or can't reach the tower. Their portables (which were Ericsson I believe) often had to go through several batteries during a single shift.
In relation to encrypted communications, I have no problem with certain encrypted communications. In narco, undercover, and stings; encrypted and unmonitored communications are a must. Also, as a former EMT and stringent requirements medical providers must go through to protect a patient's privacy, I can understand the argument that calls from the ambulance to ER (which often contain specific patient data) should be encrypted.
However, I believe encryption is a two edged sword. It limits interoperability, and during a emergency or outage...it could potentially block or prevent vital communications.
Lastly, what good is it to have an encrypted trunk id (such as EMS dispatch) that at the same time is simulcast over a VHF channel (which I believe JoCo does currently with Statewide Rescue TAC).
Again, my comments and what I know about JoCo's TRS are out of date by close to 10 years. I would love to hear some new information or experiences.