Regular police radios are frequently encrypted now. You can be damn sure DHS has been encrypting their radio traffic for decades. I can say, from personal experience, that my small hometown police started encrypting some of their radio traffic at least 40+ years ago
yeah, my small hometown (i don’t even have fiber internet small oh your gods i’m going to go on a psychotic break over this later this week aren’t i) has their encrypted channel and their unencrypted channel because they know all us dorks are and have been listening for decades. when the town almost burned down a few years back, the unencrypted channel was how the last minute volunteer emergency services got a shitton of extra fire breaks mowed across the county fuck your property lines style and kept most of the town intact
yeah, my small hometown (i don’t even have fiber internet small oh your gods i’m going to go on a psychotic break over this later this week aren’t i) has their encrypted channel and their unencrypted channel because they know all us dorks are and have been listening for decades. when the town almost burned down a few years back, the unencrypted channel was how the last minute volunteer emergency services got a shitton of extra fire breaks mowed across the county fuck your property lines style and kept most of the town intact