Vienna-area residents and reporters lost the ability to monitor Fairfax County Police Department activity through public scanners and online streaming services after FCPD encrypted its eight primary dispatch channels on Monday.

The City of Fairfax Police Department made the same move simultaneously, according to FCPD and a Fairfax City police press release issued Friday. The encrypted channels, which loosely correspond to FCPD district stations, including the Sully and McLean districts covering Vienna, can now only be heard by individuals with police-issued radios or a cryptographic key.

FCPD leaders told the Fairfax County Board of Supervisors in March that they planned to encrypt the eight main channels used by dispatchers to communicate with officers responding to crimes and other public safety calls. The department had already encrypted some side channels used for specialized units and "elevated events."

The City of Fairfax Police Department said encryption protects sensitive information routinely communicated by radio, including names, home addresses, dates of birth and medical details. The department also cited concerns about real-time monitoring through scanner apps being redistributed to individuals seeking to interfere with police operations.

Larry Calhoun, an independent public safety reporter who covers the region, pushed back. "I do believe that encryption absolutely hurts transparency from the police agencies to the public," Calhoun said, adding that delayed dispatches rather than full encryption could preserve public access while addressing officer safety concerns.

What remains public

An automated dispatch feed that sends preliminary information based on 911 calls and response requests has not been affected, according to FCPD.

Fairfax County Fire and Rescue Department frequencies also remain unencrypted. A department spokesperson said the agency does "not have any plans in the future to encrypt our primary radio channels."

Broader trend

Loudoun County law enforcement also began encrypting radio traffic on Monday, according to FFXnow reporting. Arlington County Police, Prince William County Police, Virginia State Police, and D.C.'s Metropolitan Police Department have already fully or partially encrypted their channels.

Fairfax County maintains an emergency alert system at fairfaxcounty.gov/alerts. Fairfax City police releases weekly briefings with incident summaries and maintains its own alert system.