There's a TON more to the Knox system that meets the eye.
When they built that, there was underhandedness in how it rolled out. There were not enough towers, and they had to beg people to jump onto the system to have enough users.
Then, some county deputies almost got killed due to a mile wide dead spot, forcing a system redesign.
Central Communications and the system owners have been under the table buddies for years.
When the Harris thing popped up, I laughed, because I knew that the little clique would never let that fly, and they didn't. The people that should have been attending meetings didn't, sent some people that didn't know better, and just rubberstamped whatever these underlings brought back.
SO
they had to do a bunch of backpedalling at the last minute, and unapprove the Harris deal. Unless Harris properly bribes the Sheriff and a couple other key players, there won't be anything in there but batwings.
That system is rickety, though. Previous Sheriff built his own radio system to the tune of thousands and thousands of secret dollars trying to get away from e911 for whatever his reason. It sits today, doing pretty much nothing. I think maybe they are running in car data off of one of the channels, but don't quote me.
Far as the encryption, I tried and tried to get people to call their state reps, and tried to get a law passed mandating as little encrypting as necessary, but no one wanted to help. So, now the roane county highway department is typically encrypted. Because they can.
Ah well.