I would agree with this but in most cases it depends on what the agency does. I work for a federal agency that has responsibility for emergency response and management of disasters and ALL of our comms are encrypted 100% of the time.
The federal agencies I am monitoring are(mostly) involved with criminal law enforcement. Considering what
theydo, and the fact a number of their targets employ surveillance detection/counter-surveillance and/or are violent criminals, it stands to reason they have quite the operational need for encryption.
A couple of these agencies, routinely use encryption during this type of work, and occasionally, operator error(i.e. radio user not manually turning their encryption on) is the cause of clear communications. Other times though, these same agencies just plain have it turned off and talk in the clear, even while on an operation. Another agency, whose name includes the word "Secret" in their title very rarely ever use encryption. And one more agency, who routinely conduct surveillance like described above, practically never use encryption during their operations.
Of course, this is just my experience for my area, and I know that in other parts of the country these same agencies use full time encryption, or nearly so. I can understand why a government agency of your type would want secure communications, but I don't think you can draw that same conclusion everywhere else. Obviously your chain of command has made the decision of secure communications for you and your fellow employees. Other agencies apparently give their people some latitude as to making that call. Although in terms of security needs, it doesn't seem to add up that I wouldn't be able to hear what is happening in terms of a disaster in my immediate area along with federal response, but I do know where quite a bit of felony drug activity is taking place around me along with the federal interest in it, at least from the comms I hear.