U.S. Capitol Attack and Law Enforcement Use of Facial Recognition Technology
INSIGHTi
U.S. Capitol Attack and Law Enforcement Use
of Facial Recognition Technology
February 24, 2021
On January 6, 2021, U.S. Capitol security was violently breached while Congress was in session to vote
on the certification of the 2020 presidential election. Many participants in the attack reportedly intended
to disrupt this process. Some clashed with law enforcement, leaving five dead and many more injured.
Some have been charged with violations including crimes against persons and federal property. Some
al egedly carried firearms and other weapons. Law enforcement also uncovered explosive devices near
Capitol grounds.
Participants, media, and others documented the attack on the Capitol in photographs and video. Law
enforcement, such as the Federal Bureau of Investigation (FBI), is seeking this digital content and other
evidence to assist its investigation. Among the tools that law enforcement agencies may employ to
identify potential criminal suspects depicted in digital content is facial recognition technology (FRT).
While some have reported a possible uptick in law enforcement use of FRT following the Capitol attack,
the extent to which FRT has been used to identify suspected rioters is unknown.
Law Enforcement Use of FRT
FRT, which compares images of faces using facial geometry, is one biometric tool employed by law
enforcement. FRT can be used to generate suspect leads, identify victims, sort faces in photos that are part
of forensic evidence, and verify the identity of inmates being released from prison. FRT is general y used
by law enforcement in one-to-many searches (comparing features of a probe photo with those in a
database of images) to produce a gal ery of potential suspects ranked by similarity—not a single
affirmative match.
FBI Use of FRT
The FBI operates two FRT programs: (1) the Next Generation Identification–Interstate Photo System (NGI-IPS), largely
supporting state and local law enforcement; and (2) the Facial Analysis, Comparison, and Evaluation (FACE) Services Unit,
supporting FBI investigations.
NGI-IPS contains criminal mugshots, and the system al ows authorized law enforcement users to search probe photos
of unknown persons against faces in the database for potential investigative leads.
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The FACE Services Unit searches probe photos against faces in NGI-IPS and other authorized federal and state facial
recognition systems.
A facial recognition search alone cannot provide law enforcement with a positive identification; the results must be manual y
reviewed and compared by an officer trained in facial comparison. The FBI prohibits law enforcement agencies from taking
action (e.g., making an arrest) based solely on the results of a search in NGI-IPS.
There is a patchwork of FRT systems used by federal, state, and local law enforcement agencies around
the country—including those investigating the Capitol attack. Each has its own database of faces against
which probes may be compared, and law enforcement agencies may have differing policies governing
FRT use. For instance, federal law enforcement agencies and authorized users of their FRT systems must
general y follow established FRT policies and guidelines, which may not apply to state and local law
enforcement agencies’ FRT systems.
Federal law enforcement agencies have previously used FRT to identify individuals suspected of criminal
activity associated with protests. Federal agencies investigating the Capitol attack have not confirmed
specific use of FRT but have confirmed reviewing photo and video footage. State and local law
enforcement, and individuals and companies, may also use FRT to help identify suspected Capitol
rioters—tips that they may provide to law enforcement.
Concerns over the use of FRT include the accuracy or reliability of FRT systems, public notification
regarding the use of FRT, and policies governing law enforcement agencies’ use of the technology.
Concerns surfaced following reports that Clearview AI, a company that developed image-search
technology used by law enforcement agencies around the country, had amassed a database of over 3
bil ion images against which probe photos could be compared. Some concerns have manifested in federal,
state, and city efforts to prohibit or bound law enforcement agencies’ use of FRT. Further, some
companies producing facial recognition software have enacted barriers to law enforcement using their
technologies.
Legislative Considerations
FRT can be a powerful investigative tool for law enforcement. But some observers have voiced concern
about the technology’s current and prospective use. While FRT’s reliability has improved over time, the
accuracy rates of FRT systems vary, particularly in identifying persons in certain demographic groups,
leading some to express concern regarding possible misidentification. Some have also expressed concern
that FRT—when paired with other tools and databases that contain mil ions of face images—could enable
surveil ance that encroaches on personal privacy and civil liberties. Others contend that these concerns are
overstated and may not justify curtailing law enforcement’s use of this investigative tool.
Several bil s in the 116th Congress sought to regulate the use of FRT by the government or commercial
entities, with most seeking to constrain its use. Several bil s would also have sought to influence how
state and local police use FRT by conditioning the receipt of criminal justice grants upon compliance with
certain guidelines. Since the Capitol attack, there has been considerable discussion of whether police use
of FRT to identify suspected participants wil inform policymakers’ assessment of whether to encourage
or constrain the police use of FRT in the future.
Congress has not enacted legislation specifical y addressing FRT. Outside the border security context, the
most pertinent federal laws address the collection and storage of personal data by government agencies or
commercial entities general y, though many such laws do not constrain information shared for law
enforcement purposes. State and local regulation of FRT, in turn, varies considerably. While many state
and local governments widely employ FRT, others expressly prohibit or limit its use. And although the
Constitution provides baseline parameters for FRT’s use by government actors, these considerations may
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be more relevant to assessments of the technology’s use in a particular investigation than to FRT’s general
development and deployment.
Author Information
Kristin Finklea
Kelsey Y. Santamaria
Specialist in Domestic Security
Legislative Attorney
Disclaimer
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