Covert listening device

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Listening devices of the East German security services. MfS wanzen.jpg
Listening devices of the East German security services.

A covert listening device, more commonly known as a bug or a wire, is usually a combination of a miniature radio transmitter with a microphone. The use of bugs, called bugging, or wiretapping is a common technique in surveillance, espionage and police investigations.


Self-contained electronic covert listening devices came into common use with intelligence agencies in the 1950s, when technology allowed for a suitable transmitter to be built into a relatively small package. By 1956, the US Central Intelligence Agency was designing and building "Surveillance Transmitters" that employed transistors, which greatly reduced the size and power consumption. With no moving parts and greater power efficiency, these solid-state devices could be operated by small batteries, which revolutionized the process of covert listening.

A bug does not have to be a device specifically designed for the purpose of eavesdropping. For instance, with the right equipment, it is possible to remotely activate the microphone of cellular phones, even when a call is not being made, to listen to conversations in the vicinity of the phone. [1] [2] [3] [4] [5] [6]


Among the earliest covert listening devices used in the United States of America was the dictograph, an invention of Kelley M. Turner patented in 1906 (US Patent US843186A). [7] It consisted of a microphone in one location and a remote listening post with a speaker that could also be recorded using a phonograph. While also marketed as a device that allowed broadcasting of sounds, or dictating text from one room to a typist in another, it was used in several criminal investigations. [8] [9]

A wire

A "wire" is a device that is hidden or concealed under a person's clothes for the purpose of covertly listening to conversations in proximity to the person wearing the "wire". Wires are typically used in police sting operations in order to gather information about suspects. [10] The wire device transmits to a remote location where law enforcement agents monitor what is being said.

The act of "wearing a wire" refers to a person knowingly recording the conversation or transmitting the contents of a conversation to a police listening post. Usually, some sort of device is attached to the body in an inconspicuous way, such as taping a microphone wire to their chest. Undercover agents "wearing a wire" is a typical plot element in gangster and police-related movies and television shows. A stereotypical scene might include an individual being suspected by criminals of "wearing a wire", resulting in their tearing the suspect's shirt open to reveal the deception. [11]

When infiltrating a criminal organization a mole may be given a "wire" to wear under their clothes.

Wearing a wire is viewed as risky since discovery could lead to violence against the mole or other retaliatory responses. [12]

Remotely activated mobile phone microphones

Mobile phone (cell phone) microphones can be activated remotely, without any need for physical access. [1] [2] [3] [4] [5] [6] [13] This "roving bug" feature has been used by law enforcement agencies and intelligence services to listen in on nearby conversations. [14] A United States court ruled in 1988 that a similar technique used by the FBI against reputed former Gulfport, Mississippi, cocaine dealers after having obtained a court order was permissible. [15] Not only microphones but also seemingly innocuous motion sensors, which can be accessed by third-party apps on Android and iOS devices without any notification to the user, are a potential eavesdropping channel in smartphones. [1] With the Covid-19 pandemic came an increase in remote work spurring on a new advent of Employee Monitoring Software which remotely collects many forms of data from laptops and smartphones issued by employers, including webcam and microphone data, raising concerns that a new era of corporate spying has shifted the power balance between workers and businesses.

Automobile computer systems

In 2003, the FBI obtained a court order to surreptitiously listen in on conversations in a car through the car's built-in emergency and tracking security system. A panel of the 9th Circuit Court of Appeals prohibited the use of this technique because it involved deactivating the device's security features. [16] [17]

Audio from optical sources

A laser microphone can be used to reconstruct audio from a laser beam shot onto an object in a room, or the glass pane of a window.

Researchers have also prototyped a method for reconstructing audio from video of thin objects that can pick up sound vibrations, such as a houseplant or bag of potato chips. [18]

Examples of use

Listening devices and the UK law

The use of listening devices is permitted under UK law providing that they are used in compliance with Data Protection and Human Rights laws. If a government body or organisation intends to use listening or recording devices they must follow the laws put in place by the Regulation of Investigatory Powers Act (RIPA). It is usually permitted to record audio covertly in a public setting or one's own home.

It is illegal to use listening or recording devices that are not permitted for public use. Individuals may only use listening or recording devices within reasonable privacy laws for legitimate security and safety reasons. Many people use listening devices on their own property to capture evidence of excessive noise in a neighbour complaint, which is legal in normal circumstances. [35]

It is legal to use listening or recording devices in public areas, in an office or business area, or in one's own home. Many people use listening devices to record evidence or to take notes for their own reference. [35]

Illegal use of listening and recording devices

It is illegal to use listening devices on certain Military band and Air Band UHF and FM frequencies - people in the past who have not followed this law have been fined over £10,000. This is because the use of a radio transmission bug that transmits on restricted frequencies contravenes the Telecommunications Act and is illegal. It is also against the law to place a listening or recording device in someone else's home. Due to privacy and human rights laws, using a listening or recording device to intrude on the reasonable expectation of privacy of an individual is highly illegal, i.e. placing gadgets in someone's home or car to which one does not have permitted access, or in a private area such as a bathroom.

United States Law on Listening Devices

Federal laws on Listening Devices

Several federal laws were passed by congress that apply nation-wide. Under Title 18 of the US Code § 2251 2(iii)(c) at least one of the parties involved in the communication must have given consent to interception of the communication. This title applies to wire, oral, or any kind of electric communication. This single party consent only applies if one of the parties is an "officer of the United States" (Title 18 of the US Code § 2251 [2d]). [36] Furthermore, congress passed the Electronic Communications Privacy Act of 1986 (ECPA). This act updated the Federal Wiretap Act of 1968. The Federal Wiretap act addressed the interception of conversations over telephone lines, but not interception of computer or other digital data. This act was further updated by the USA Patriot Act to clarify and modernize the ECPA. The ECPA has three title. Title I prohibits attempted or successful interception of or "procure[ment] [of] any other person to intercept or endeavor to intercept any wire, oral, or electronic communication." It also prohibits the storage of any information obtained via phone calls without consent or illegally obtained though wiretaps. [37] Furthermore, the US passed the Wiretap Act which prohibits unauthorized interception of "wire, oral, or electronic communications" by the government or by private citizens. Furthermore, this act establishes the procedure for government officials to obtain warrants to authorize any wiretapping activates. Such laws were passed in response to congressional investigations that found extensive cases of government and private wiretapping without consent or legal authorization. [38] In the US electronic surveille is seen as protected under the Constitution that the Fourth Amendment, which protects against unreasonable search and seizure by the government, [39] which also is seen by the Supreme Court of the United States as electronic surveille.

State to State variation

Listening devices are regulated by several legislative bodies in the United States. Laws on listening devices varies between states within the US. Typically the variation comes on whether or not the state is a one or two party consent state. Within one party consent states, only one party must approve the recording, whereas in all party consent states all parties must consent to the recording. In many states, the consent requirements listed below only apply to situations where the parties have a reasonable expectation of privacy, such as private property, and do not apply in public areas. [40] (Protection can apply to conversations in public areas in some circumstances.) [41]

Parties required to give consent by state
One-party Consent StatesAll-Party Consent States
District of Columbia (D.C.)Maryland
IowaNew Hampshire
New Jersey
New Mexico
New York
North Carolina
North Dakota
Rhode Island
South Carolina
South Dakota
West Virginia

See also

Related Research Articles

<span class="mw-page-title-main">Surveillance</span> Monitoring something for the purposes of influencing, protecting, or suppressing it

Surveillance is the monitoring of behavior, many activities, or information for the purpose of information gathering, influencing, managing or directing. This can include observation from a distance by means of electronic equipment, such as closed-circuit television (CCTV), or interception of electronically transmitted information like Internet traffic. It can also include simple technical methods, such as human intelligence gathering and postal interception.

Wiretapping, also known as wire tapping or telephone tapping, is the monitoring of telephone and Internet-based conversations by a third party, often by covert means. The wire tap received its name because, historically, the monitoring connection was an actual electrical tap on an analog telephone or telegraph line. Legal wiretapping by a government agency is also called lawful interception. Passive wiretapping monitors or records the traffic, while active wiretapping alters or otherwise affects it.

Computer and network surveillance is the monitoring of computer activity and data stored locally on a computer or data being transferred over computer networks such as the Internet. This monitoring is often carried out covertly and may be completed by governments, corporations, criminal organizations, or individuals. It may or may not be legal and may or may not require authorization from a court or other independent government agencies. Computer and network surveillance programs are widespread today and almost all Internet traffic can be monitored.

<span class="mw-page-title-main">Hidden camera</span> Type of surveillance camera

A hidden camera or spy camera is a camera used to photograph or record subjects, often people, without their knowledge. The camera may be considered "hidden" because it is not visible to the subject being filmed, or is disguised as another object. Hidden cameras are often considered a surveillance tool.

A pen register, or dialed number recorder (DNR), is a device that records all numbers called from a particular telephone line. The term has come to include any device or program that performs similar functions to an original pen register, including programs monitoring Internet communications.

<span class="mw-page-title-main">Omnibus Crime Control and Safe Streets Act of 1968</span> US federal legislation

The Omnibus Crime Control and Safe Streets Act of 1968 was legislation passed by the Congress of the United States and signed into law by President Lyndon B. Johnson that established the Law Enforcement Assistance Administration (LEAA). Title III of the Act set rules for obtaining wiretap orders in the United States. The act was a major accomplishment of Johnson's war on crime.

<span class="mw-page-title-main">Electronic Communications Privacy Act</span> 1986 United States federal law

The Electronic Communications Privacy Act of 1986 (ECPA) was enacted by the United States Congress to extend restrictions on government wire taps of telephone calls to include transmissions of electronic data by computer, added new provisions prohibiting access to stored electronic communications, i.e., the Stored Communications Act, and added so-called pen trap provisions that permit the tracing of telephone communications . ECPA was an amendment to Title III of the Omnibus Crime Control and Safe Streets Act of 1968, which was primarily designed to prevent unauthorized government access to private electronic communications. The ECPA has been amended by the Communications Assistance for Law Enforcement Act (CALEA) of 1994, the USA PATRIOT Act (2001), the USA PATRIOT reauthorization acts (2006), and the FISA Amendments Act (2008)

Katz v. United States, 389 U.S. 347 (1967), was a landmark decision of the U.S. Supreme Court in which the Court redefined what constitutes a "search" or "seizure" with regard to the protections of the Fourth Amendment to the U.S. Constitution. The ruling expanded the Fourth Amendment's protections from an individual's "persons, houses, papers, and effects", as specified in the Constitution's text, to include any areas where a person has a "reasonable expectation of privacy". The reasonable expectation of privacy standard, now known as the Katz test, was formulated in a concurring opinion by Justice John Marshall Harlan II.

The USA PATRIOT Act was passed by the United States Congress in 2001 as a response to the September 11, 2001 attacks. It has ten titles, each containing numerous sections. Title II: Enhanced Surveillance Procedures granted increased powers of surveillance to various government agencies and bodies. This title has 25 sections, with one of the sections containing a sunset clause which sets an expiration date, December 31, 2005, for most of the title's provisions. This was extended twice: on December 22, 2005 the sunset clause expiration date was extended to February 3, 2006 and on February 2 of the same year it was again extended, this time to March 10.

<span class="mw-page-title-main">NSA warrantless surveillance (2001–2007)</span> Part of Terrorist Surveillance Program

NSA warrantless surveillance — also commonly referred to as "warrantless-wiretapping" or "-wiretaps" — was the surveillance of persons within the United States, including U.S. citizens, during the collection of notionally foreign intelligence by the National Security Agency (NSA) as part of the Terrorist Surveillance Program. In late 2001, the NSA was authorized to monitor, without obtaining a FISA warrant, phone calls, Internet activities, text messages and other forms of communication involving any party believed by the NSA to be outside the U.S., even if the other end of the communication lays within the U.S.

<span class="mw-page-title-main">Terrorist Surveillance Program</span> NSA program

The Terrorist Surveillance Program was an electronic surveillance program implemented by the National Security Agency (NSA) of the United States in the wake of the September 11, 2001 attacks. It was part of the President's Surveillance Program, which was in turn conducted under the overall umbrella of the War on Terrorism. The NSA, a signals intelligence agency, implemented the program to intercept al Qaeda communications overseas where at least one party is not a U.S. person. In 2005, The New York Times disclosed that technical glitches resulted in some of the intercepts including communications which were "purely domestic" in nature, igniting the NSA warrantless surveillance controversy. Later works, such as James Bamford's The Shadow Factory, described how the nature of the domestic surveillance was much, much more widespread than initially disclosed. In a 2011 New Yorker article, former NSA employee Bill Binney said that his colleagues told him that the NSA had begun storing billing and phone records from "everyone in the country."

Telephone call recording laws are legislation enacted in many jurisdictions, such as countries, states, provinces, that regulate the practice of telephone call recording. Call recording or monitoring is permitted or restricted with various levels of privacy protection, law enforcement requirements, anti-fraud measures, or individual party consent.

[[File:|thumb|Locations of CIA/NSA Special Collection Service (SCS) eavesdropping sites in 2004]] [[File:|thumb|Location and status of CIA/NSA Special Collection Service (SCS) eavesdropping sites as of August 13, 2010]]

Telephone tapping in the Eastern Bloc was a widespread method of the mass surveillance of the population by the secret police.

<span class="mw-page-title-main">Digital Collection System Network</span>

The Digital Collection System Network (DCSNet) is the Federal Bureau of Investigation (FBI)'s point-and-click surveillance system that can perform instant wiretaps on almost any telecommunications device in the United States.

Countersurveillance refers to measures that are usually undertaken by the public to prevent surveillance, including covert surveillance. Countersurveillance may include electronic methods such as technical surveillance counter-measures, which is the process of detecting surveillance devices. It can also include covert listening devices, visual surveillance devices, and countersurveillance software to thwart unwanted cybercrime, such as accessing computing and mobile devices for various nefarious reasons. More often than not, countersurveillance will employ a set of actions (countermeasures) that, when followed, reduce the risk of surveillance. Countersurveillance is different from sousveillance, as the latter does not necessarily aim to prevent or reduce surveillance.

<span class="mw-page-title-main">Cellphone surveillance</span> Interception of mobile phone activity

Cellphone surveillance may involve tracking, bugging, monitoring, eavesdropping, and recording conversations and text messages on mobile phones. It also encompasses the monitoring of people's movements, which can be tracked using mobile phone signals when phones are turned on.

Network eavesdropping, also known as eavesdropping attack, sniffing attack, or snooping attack, is a method that retrieves user information through the internet. This attack happens on electronic devices like computers and smartphones. This network attack typically happens under the usage of unsecured networks, such as public wifi connections or shared electronic devices. Eavesdropping attacks through the network is considered one of the most urgent threats in industries that rely on collecting and storing data. Internet users use eavesdropping via the Internet to improve information security.

A microphone blocker is a phone microphone connector used to trick feature phones that have a physical microphone switch to disconnect the microphone. Microphone blockers won't operate on smartphones or laptops because the microphone is controlled with software rather than a physical switch.


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