I'll copy my reply to the above, but add that someone who has the key to encrypt a broadcast doesn't necessarily have a need to receive private health information. Law enforcement officials may receive protected information if they need it in the course of their duties. Private health information should only be shared in a secure communication, but encrypting the broadcast doesn't change the fact that

This is like HIPAA training 101 stuff. If you're a doctor at a hospital, you might be able to access any patient's records. But if you peek at a celebrity's serologies, you've violated HIPAA. Broadcasting on an encrypted channel would be like posting test results in a locker room and arguing that it's OK because only doctors have a key to the room. Having access to information is not the same as needing access to information, regardless of whether everyone has their paperwork in order.

That's absurd. There are very specific guidelines for sharing protected health information with and among law enforcement. There is no paperwork that "all receiving parties" can fill out to cover a blanket broadcast of protected information to anyone with an encrypted police radio. You would still need to have a specific purpose for disclosure, and disclose only the required information to only the necessary parties. An encrypted channel would still be available to dispatchers, administrators, and a bunch of random people that don't need to receive that information.

Covered entities may disclose protected health information to law enforcement officials for law enforcement purposes under the following six circumstances, and subject to specified conditions: (1) as required by law (including court orders, court-ordered warrants, subpoenas) and administrative requests; (2) to identify or locate a suspect, fugitive, material witness, or missing person; (3) in response to a law enforcement official's request for information about a victim or suspected victim of a crime; (4) to alert law enforcement of a person's death, if the covered entity suspects that criminal activity caused the death; (5) when a covered entity believes that protected health information is evidence of a crime that occurred on its premises; and (6) by a covered health care provider in a medical emergency not occurring on its premises, when necessary to inform law enforcement about the commission and nature of a crime, the location of the crime or crime victims, and the perpetrator of the crime.34

https://www.hhs.gov/hipaa/for-professionals/privacy/laws-regulations/index.html