The current status of Federal Communications in any given area comes down to funding.
Officially, they're ALL supposed to be converted to P25/Encrypted (at least capable) by now, narrowband.
In fact, not all areas are, yet.
San Diego County feds converted to all-encrypted back when the Olympics came to San Diego, resulting in a huge swatch of funding to upgrade their systems at that time. Los Angeles, right next door, did not get the funding, and is (supposedly) still rarely encrypted.
Some parts of some agencies resist the trends. US Customs Aircraft tend to stay in the clear, it seems that high-speed movement is hard on digital syncronization or somesuch. This can result in you hearing a 'chase' where the helicopter doing most of the calling of suspect location is 'in the clear', while those talking to him are encrypted.
There are often things out there most would never think of, which are usually quiet, but might, some day, be spectacular...
If you're in range of a US Naval anchorage where many ships are in port, try plugging in 328.2 AM. Listen around sunrise and sunset (official). If you hear a countdown to colors, congratulations, you're listening to the Fleet Warning channel. Most of the time, it's quiet, routine check ins, etc. Ah, but SOMEtimes....
You see, this is the ONLY radio net Ships in port at anchor monitor externally, other than their own internal work group radios. It's the way the local command notifies them of incoming messages. If the USA changes DEFCON, it will be communicated immediately to the ships, here. If someone has reported swimmers in the water with suspicious packages, suspected terrorists, it will come out here, immediately. One quiet little channel, rarely listened to, or known, to most scanner types... but if you have it in, and something happens... You'll know as fast at the Navy does.