The United States has a complex and expanding network of surveillance systems, encompassing physical and digital monitoring by federal and local agencies for purposes like national security, law enforcement, and immigration enforcement

. Technologies include border surveillance systems (like radar, thermal imaging, and sensors), mass surveillance programs run by the National Security Agency (NSA), city-wide facial recognition networks, and the monitoring of financial transactions and social media. These systems raise significant constitutional and privacy concerns due to their scale and potential for misuse. 

Types of surveillance systems

• Border Surveillance: The Department of Homeland Security (DHS) uses a variety of technologies to monitor the border, including fixed and mobile video surveillance, radar, ground sensors, and thermal imaging. Customs and Border Protection (CBP) also uses tools to monitor U.S. drivers for suspicious travel patterns, with systems collecting license plate data and using other technologies.
• National Security Surveillance: The NSA conducts mass surveillance, including monitoring international communications like emails and text messages, a practice that has expanded significantly over time. Some programs, like those authorized under Section 702 of the Foreign Intelligence Surveillance Act (FISA), involve targeting a large number of individuals, groups, and organizations, and have led to the retention of millions of internet communications.
• Law Enforcement and Criminal Investigations:
  • Facial Recognition: Several cities have deployed or are piloting city-wide facial surveillance networks, which can scan people’s faces in real time as they move through public spaces.
  • Social Media Monitoring: Federal agencies, including the FBI and components of DHS, monitor public social media to assist with investigations, detect threats, and maintain situational awareness.
  • Automated License Plate Readers (ALPR):Some companies sell cloud-connected camera systems that police can use for ALPR. This data can be shared with other agencies, including ICE, for immigration enforcement purposes.
• Financial Surveillance: Reports indicate that federal law enforcement, including the Financial Crimes Enforcement Network (FinCEN) and the FBI, have engaged in broad surveillance of Americans’ financial data, sometimes using backchannel discussions with financial institutions. 

Concerns and controversies

• Constitutional Rights: Critics argue that mass surveillance infringes on Fourth Amendment rights against unreasonable searches and raises concerns about privacy, free speech, and due process.
• Scope and Scale: The sheer volume of data collected, such as communications and license plate information, raises concerns about the government’s ability to monitor a vast number of people, even those not suspected of wrongdoing.
• Lack of Transparency: The government has been criticized for a lack of transparency regarding the scale of its surveillance programs and the data collected.
• Potential for Abuse: There are concerns that powerful surveillance tools can be abused, leading to the inclusion of innocent individuals on watchlists, disproportionate targeting of minority communities, and the use of surveillance for political purposes.