Information about Telephone Tapping

Telephone tapping (or wire tapping/wiretapping in the US) is the monitoring of telephone and Internet conversations by a third party, often by covert means. The telephone tap or wire tap received its names because historically, the monitoring connection was applied to the wires of the telephone line of the person who was being monitored and drew off or tapped a small amount of the electrical signal carrying the conversation. Legalized wiretapping by police or other recognized governmental authority is otherwise known as lawful interception.

Passive wiretapping only attempts to observe the flow and gain knowledge of the information it contains. Active wiretapping attempts to alter the data or otherwise affect the flow of data.

Legal status

Main article: Telephone recording laws

Telephone tapping is officially strictly controlled in many countries to safeguard an individual's privacy; this is the case in all developed democracies. In theory, telephone tapping often needs to be authorised by a court, and is, again in theory, normally only approved when evidence shows it is not possible to detect criminal or subversive activity in less intrusive ways; often the law and regulations require that the crime investigated must be at least of a certain severity. In many jurisdictions however, permission for telephone tapping is easily obtained on a routine basis without further investigation by the court or other entity granting such permission. Illegal or unauthorised telephone tapping is often a criminal offense. However, in certain jurisdictions such as Germany, courts will accept illegally recorded phone calls without the other party's consent as evidence.

In the United States, federal agencies may be authorized to engage in wiretaps by the United States Foreign Intelligence Surveillance Court, a court with secret proceedings, in certain circumstances.

Under United States federal law and most state laws there is nothing illegal about one of the parties to a telephone call recording the conversation, or giving permission for calls to be recorded or permitting their telephone line to be tapped. However the Telephone recording laws in some U.S. states require only one party to be aware of the recording, while other states require both parties to be aware. It is considered better practice to announce at the beginning of a call that the conversation is being recorded.

In India, telephone tapping has to be approved by a designated authority. It is illegal otherwise.

Methods

Official use

Main article: Lawful interception

The contracts or licenses by which the state controls telephone companies often require that the companies must provide access for tapping lines to the security services and the police. In the U.S., telecommunications carriers are required by law to cooperate in the interception of communications for law enforcement purposes under the terms of CALEA.

When telephone exchanges were mechanical, a tap had to be installed by technicians, linking circuits together to route the audio signal from the call. Now that many exchanges have been converted to digital technology tapping is far simpler and can be ordered remotely by computer. Telephone services provided by cable TV companies also use digital switching technology. If the tap is implemented at a digital switch, the switching computer simply copies the digitized bits that represent the phone conversation to a second line and it is impossible to tell whether a line is being tapped. A well-designed tap installed on a phone wire can be difficult to detect. The noises that some people believe to be telephone taps are simply crosstalk created by the coupling of signals from other phone lines.

Data on the calling and called number, time of call and duration, will generally be collected automatically on all calls and stored for later use by the billing department of the phone company. These data can be accessed by security services, often with fewer legal restrictions than for a tap. This information used to be collected using special equipment known as pen registers and trap and trace devices and U.S. law still refers to it under those names. Today, a list of all calls to a specific number can be obtained by sorting billing records. A telephone tap during which only the call information is recorded but not the contents of the phone calls themselves, is called a pen register tap.

For telephone services via digital exchanges, the information collected may additionally include a log of the type of communications media being used (some services treat data and voice communications differently to conserve bandwidth).

Unofficial use

It is also possible to tap conversations unofficially. There are a number of ways to monitor telephone conversations:

• Recording the conversation - the person making/receiving the call records the conversation using a coil tap (telephone pickup coil) attached to the ear-piece, or they fit an in-line tap with a recording output. Both of these are easily available through electrical shops. A more modern alternative is to use telephone recording devices connected to computers, such as call recording software.
• Direct line tap - involves a direct electrical connection to the line using a Butt set or a Beige box (phreaking), or an induction coil. An induction coil is usually placed underneath the base of a telephone or on the back of a telephone handset to pick up the signal inductively. With a direct connection, there will be some drop in signal levels because of the loss of power from the line, and it may also generate noise on the line. A well designed induction tap does not drain voltage or current from the line because it isn't physically connected to the phone line. Direct taps sometimes require regular maintenance, either to change tapes or replace batteries, which may give away their presence.
• Radio tap - this is like a bug that fits on the telephone line. It can be fitted to one phone inside the house, or outside on the phone line. It may produce noise (there might even be signal feedback on the monitored line on poorly made equipment) to inadvertently alert the caller. Modern state of the art equipment operates in the 30-300 GHz range. The unit is powered from the line to be maintenance free, and only transmits when a call is in progress. These devices tend to be low powered because the drain on the line would become too great, however a state of the art receiver could be located as far away as ten kilometers under ideal conditions, but is usually located within a radius of 1 to 3 km. Research however has also shown that a satellite can be used to receive emissions in the range of a few milliwatts.

Location data

Mobile phones are, in surveillance terms, a major liability. This liability will only increase as the new third-generation (3G) phones are introduced, as the base stations will be located closer together. For mobile phones the major threat is the collection of communications data. This data is not only include information about the time, duration, originator and recipient of the call, but also the identification of the base station where the call was made from, which equals its approximate geographical location. This data is stored with the details of the call and has utmost importance for traffic analysis.

It is also possible to get greater resolution of a phone's location by combining information from a number of cells surrounding the location, which cells routinely communicate (to agree on the next handoff—for a moving phone) and measuring the timing advance, a correction for the speed of light in the GSM standard. This additional precision must be specifically enabled by the telephone company - it is not part of ordinary operation.

The second generation mobile phones (circa 1978 through 1990) could be easily monitored by anyone with a 'scanning all-band receiver' because the system used an analog transmission system-like an ordinary radio transmitter. The third generation digital phones are harder to monitor because they use digitally-encoded and compressed transmission. However the government can tap mobile phones with the cooperation of the phone company. It is also possible for organizations with the correct technical equipment to monitor mobile phone communications and decrypt the audio. A device called an "IMSI-catcher" pretends to the mobile phones in its vicinity to be a legitimate base station of the mobile phone network, subjecting the communication between the phone and the network to a man in the middle attack. This is possible because while the mobile phone has to authenticate itself to the mobile telephone network, the network does not authenticate itself to the phone. This security hole was intentionally introduced to facilitate eavesdropping without the knowledge or cooperation of the mobile phone network. Once the mobile phone has accepted the IMSI-catcher as its base station the IMSI-catcher can deactivate GSM encryption using a special flag. All calls made from the tapped mobile phone go through the IMSI-catcher and are then passed on to the mobile network. Some phones include a special monitor mode (activated with secret codes or special software) which displays GSM operating parameters such as encryption while a call is being made. There is no defense against IMSI-catcher based eavesdropping, except using end-to-end call encryption; products offering this feature, secure telephones, are already beginning to appear on the market, though they tend to be expensive and incompatible with each other, which limits their proliferation.

There were proposals for European mobile phones to use stronger encryption, but this was opposed by a number of European countries, including the Netherlands and Germany, which are among the world's most prolific telephone tappers (over 10,000+ phone numbers in both countries in 2003).

One-ring calls

These calls cannot be recognized by caller ID as a CID displays the caller's number only between the first two rings. The purpose of a one-ring call is usually to determine if a person is using the phone. Accessing the telephone exchange is the only way to determine the origin of these calls.

Internet

While a Special Agent with the Naval Criminal Investigative Service, Peter Garza conducted the first court-ordered Internet wiretap in the United States while investigating the Julio Cesar Ardita ("El Griton") cracking case.

As technologies emerge, including VOIP, new questions are raised about law enforcement access to communications, see Voip recording.

The Internet Engineering Task Force has decided not to consider requirements for wiretapping as part of the process for creating and maintaining IETF standards (RFC 2804).

History

During the American Civil War, government officials under President Abraham Lincoln eavesdropped on telegraph conversations. Telephone wiretapping began in the 1890s, following the invention of the telephone recorder. Wiretapping has also been carried out under most Presidents, usually with a lawful warrant since the Supreme Court ruled it constitutional in 1928. Domestic wiretapping under the Clinton administration led to the capture of Aldrich Ames, a former Soviet spy in 1994. Robert F. Kennedy monitored the activity of Martin Luther King Jr. by wiretapping in 1966.

Before the Japanese attack on Pearl Harbor and the subsequent entry of the United States into World War II, the U.S. House of Representatives held hearings on the legality of wiretapping for national defense. Significant legislation and judicial decisions on the legality and constitutionality of wiretapping had taken place years before World War II.^[1] However, it took on new urgency at that time of national crisis.The actions of the government regarding wiretapping for the purpose of national defense in the current war on terror have drawn considerable attention and criticism. In the World War II era, the public was also aware of the controversy over the question of the constitutionality and legality of wiretapping. Furthermore, the public was concerned with the decisions that the legislative and judicial branches of the government were making regarding wiretapping.^[2]

In the Greek telephone tapping case 2004-2005 more than 100 mobile phone numbers belonging mostly to members of the Greek government, including the Prime Minister of Greece, and top-ranking civil servants were found to have been illegally tapped for a period of at least one year. The Greek government concluded this had been done by a foreign intelligence agency, for security reasons related to the 2004 Olympic Games, by unlawfully activating the lawful interception subsystem of the Vodafone Greece mobile network.

The most recent case of U.S. wiretapping was the NSA warrantless surveillance controversy discovered in December 2005. It aroused much controversy, after several people accused President George W. Bush of violating a specific federal statute (FISA) and the United States Constitution. The president argued his authorization was consistent with other federal statutes (AUMF) and other provisions of the Constitution, was necessary to keep America safe from terrorism, and could lead to the capture of notorious terrorists responsible for 9/11.

See also

• CALEA
• Mass surveillance
• Nixon Attorney General John Mitchell
• Pen register
• Privacy
• Privacy International
• United States v. U.S. District Court
• Hepting vs. AT&T (a 2006 lawsuit in which the Electronic Frontier Foundation alleges AT&T allowed the NSA to tap the entirety of its clients' internet and Voice over IP communications)
• Telephone tapping in the Eastern Bloc

References

External links

• A guide to whether phone conversations can be taped in the United States
• Administrative Office of the United States Courts reports on phone tapping
• RFC 2804
• How Stuff Works: A guide on wiretapping, how it works and links to other resources.
• Bugging and Tape Recording Conversations in Arizona: Is it Legal?
• List of U.S. States with two party or one party consent laws
• Guide to lawful intercept legislation around the world
• Privacy Laws by State