Over the past months, federal law enforcement has used a wide variety of surveillance technologies to track down rioters who participated in the 6 January attack on the US Capitol building – demonstrating rising surveillance across the nation.

Recent news coverage of the riot has largely focused on facial recognition – and how private citizens and local law enforcement officials have conducted their own facial recognition investigations in an attempt to assist the FBI with the help of social media. But charging documents reveal that the FBI has relied on a variety of other technologies, including license plate readers, police body cameras and cellphone tracking. And civil rights watchdogs like the ACLU are concerned that the same technologies used to surveil the rioters could impede protesters exercising their first amendment rights.

The Capitol riot was an exceptional event – marking the first time in centuries that insurrectionists breached the center of the US federal government. Many of those surveilled and charged belonged to white supremacist groups. But, according to Dave Maass of the Electronic Frontier Foundation, a non-profit advocating for free speech and digital privacy, the level of surveillance was “overkill”.

For example, charging documents for William Vogel of Pawling, New York, showed that “numerous tipsters” contacted the FBI when they recognized him in Snapchat videos he allegedly posted to his account during the riots.

Despite having video evidence that Vogel participated in the riots, the FBI also tracked his car from his home to the riots using automatic license plate readers (ALPRs). ALPRs use artificial intelligence to log the plate number of each car that passes certain cameras – which can be attached to police cars or fixed locations like street lamps. When someone registers a vehicle, their identifying information becomes associated with their license plate number, allowing law enforcement agencies to attach their identity to their car. A custom Google search of justice department records showed that law enforcement used ALPRs to track alleged Capitol rioters in at least five cases.

ALPR use has been expanding across the nation over the last decade, making it easier for law enforcement agencies to track individual cars from state to state, as they did in Vogel’s case. A 2011 survey of 70 law enforcement agencies found that almost three-quarters of agencies already had ALPRs, and that 85% planned to increase their use in the next five years.

Statistics suggest that ALPRs scan license plates at least a billion times each year in the US, and that the vast majority of the scans are not associated with a crime. The ACLU has fought for legislation on ALPRs because they are often used to track and store data of people who have not been accused of a crime. In Long Beach last year, a local publication reported that Pasadena and Riverside police used ALPRs to flag Black Lives Matter protest attendees.

Police body-worn cameras (BWCs) have also played a role in multiple Capitol riot investigations. BWCs have proliferated in the United States as part of an effort to increase police accountability. While much of the discussion surrounding BWCs in the last few years has focused on surveilling police, the cameras are often instead used as a tool for police to surveil citizens.

These cameras could infringe on legal first amendment activity. According to NPR and the Progressive, Klee Benally, an indigenous rights activist, was arrested in 2018 based on BWC footage, three weeks after rallying for Indigenous People’s Day in Flagstaff, Arizona. The protest blocked traffic, and investigators used BWC footage to determine which protesters caused the jam.

Police in Miami also used BWC footage to arrest BLM protesters weeks after the event. The ACLU has recommended that such footage should not be permissible evidence in the case of first amendment protests. The Capitol riot does not qualify as a first amendment protest as participants illegally entered a government building. However, DC Metropolitan police are permitted to use body-camera footage as evidence to arrest protesters participating in free speech activity – if they are engaged in “unlawful conduct”.

While the surveillance tools were used to monitor the mostly white crowd in the Capitol during the riots, research and news reports have indicated that Black demonstrators are more likely to be monitored during protests, and to be arrested for protest-related infractions than white demonstrators.

Christian Davenport, a political science professor at the University of Michigan, led a study of more than 15,000 protests between 1960 to 1990 to find out if race was a factor in police response to protests. Researchers found:

[W]hen compared with other groups, African American protesters are more likely to draw police presence and that once police are present they are more likely to make arrests, use force and violence, and use force and violence in combination with arrests at African American protest events.”

On top of concerns about privacy and racial inequity, Maass pointed out that rather than keeping the Capitol safer at the time of the attacks, surveillance seems to have replaced real-time police work.

“I was definitely sitting in front of the computer watching live and wondering ‘where are the cops?’ No one was kicking people out,” he said. “All the surveillance in the world didn’t serve to prevent what happened … it’s helping them clean up the mess afterwards. Surveillance is not a replacement for judgment.”