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Privacy August 13, 2026

A Brief History of Surveillance Technology

Understanding where surveillance technology came from helps predict where it’s going.

1840s-1900s: The telegraph and telephone

  • 1844: Telegraph enables long-distance communication, and the first wiretapping
  • 1876: Telephone invented. Within years, police begin tapping lines
  • 1890: Warren and Brandeis publish “The Right to Privacy” in the Harvard Law Review, the first articulation of privacy as a legal concept

1900s-1960s: Electronic surveillance

  • 1928: Olmstead v. United States: Supreme Court rules wiretapping isn’t a “search” under the Fourth Amendment
  • 1946: UKUSA Agreement (precursor to Five Eyes) established
  • 1952: NSA founded
  • 1956-1971: COINTELPRO: FBI conducts domestic surveillance of civil rights leaders, antiwar activists, and political organizations

1960s-1980s: Regulation and resistance

  • 1967: Katz v. United States: Supreme Court reverses Olmstead, recognizes “reasonable expectation of privacy”
  • 1968: Wiretap Act requires court authorization for interception
  • 1975: Church Committee exposes intelligence agency abuses
  • 1978: FISA (Foreign Intelligence Surveillance Act) creates FISA Court
  • 1986: Electronic Communications Privacy Act extends wiretap protections to electronic communications

1990s-2000s: Digital surveillance

  • 1994: CALEA: Law requiring telecom carriers to build wiretap capability into equipment
  • 1995: First commercial CCTV systems in UK cities
  • 2001: PATRIOT Act massively expands surveillance authority after 9/11
  • 2007: PRISM program begins collecting data from tech companies under Section 702

2010s: Mass surveillance revealed

  • 2013: Edward Snowden discloses NSA mass surveillance programs
  • 2014: First commercial facial recognition systems deployed by police
  • 2015: USA FREEDOM Act reforms bulk metadata collection
  • 2016: UK Investigatory Powers Act (“Snooper’s Charter”) legalizes mass surveillance
  • 2018: GDPR takes effect, establishing strongest privacy framework in history

2020s: AI-powered surveillance

  • 2020: COVID contact tracing normalizes location surveillance
  • 2022: Dobbs decision raises stakes for health and location data privacy
  • 2024: EU AI Act enters force, first comprehensive AI regulation
  • 2025: Autonomous surveillance (AI processing without human review) becomes standard

What comes next

  • Persistent surveillance from satellite constellations
  • Smart dust and nano-sensors
  • Ubiquitous biometric identification
  • AI that can infer identity from gait, posture, and behavior
  • Quantum computing threatens current encryption

Each generation of surveillance technology builds on the last. Counter-surveillance must evolve at the same pace.

See the current state of physical surveillance on Sentinel.