CDP
The Chicago Police Department has experienced jamming of its radios during protests in the city in the wake of the death of George Floyd.

Widespread anger in the US over the death of George Floyd at the hands of the Minneapolis Police Department are seeing some protestors jam police radio.

One usually associates electronic attack with the military, but it is clear from the widespread disturbances that have swept the United States in the wake of the death of George Floyd who was asphyxiated by a member of the Minneapolis Police Department on 25th May; that electronic attack is now a staple of civil unrest.

Persistent reports emerged on 30th May that some individuals involved in protests in Chicago highlighting Mr. Floyd’s plight had succeeded in jamming Chicago Police Department (CPD) communications. Local reports stated that jamming was widespread and had seen frequencies used by police radios attacked with false voice traffic and music. Recordings have even been made of Serbian folk music being broadcast over police frequencies. Dan Casey, deputy director of public safety information at the Office of Emergency Management and Communications (OEMC) for the City of Chicago, condemned the jamming as dangerous, as such activity could hamper the response of the police and emergency services to disturbances around the city.

Interestingly reports have said that most radios used by CPD officers are not encrypted and use fixed frequency transmissions. A cursory search reveals that the frequencies used by the CPD are freely available on the web. Individuals can also buy police radio scanners which will reveal the frequencies being used while radio jammers can be easily obtained on the internet. The upshot of this is that an individual with rudimentary radio knowledge can identify police frequencies and jam them. Having several individuals across a city performing similar actions could cause real headaches for law enforcement.

The obvious step would be to encrypt all police communications to outflank the jamming. However, as local reports note such proposals are controversial. The OEMC have said that some frequencies must remain clear to ensure that police departments can communicate easily with other agencies. These agencies would need to be provided with a decryption key should the traffic be encrypted. Secondly, some news organisations have protested that encryption would deprive them the means of monitoring police communications to discover and report from crime scenes. Meanwhile some civil rights campaigners have highlighted the need to monitor police communications to ensure officers can be held to account if they break the law. The OEMC has said that plans are afoot to encrypt more of the CPD’s communications, but as events in Chicago have illustrated, jamming unencrypted police radio during future disturbances looks set to become a permanent feature of civil unrest.

by Dr. Thomas Withington