Privacy Alerts - Eavesdropping, Phone Taps

Can people eavesdrop on my landline phone conversations?

Purposely listening to another's private conversation is eavesdropping. Eavesdropping can be illegal. It is an invasion of privacy. That said, it might happen more often than you think. Also, there are a growing number of technologies that enable eavesdropping.

At worst people who eavesdrop may be paranoid, obsessed, or criminal... but it does happen, so we want to share what we know with you.

In this section we will consider third parties listening to landline phone conversations at home, in public, and in the workplace. A third party is anyone who is not the intended sender or recipient of a phone communication.

So, how might someone eavesdrop lawfully/unlawfully?

1.) Your phone company and affiliates. They don't have any purpose to eavesdrop on your conversations and it's against most companies' policies. It is important to note that the phone company is required by law to cooperate with government agencies who request to access your communications.

2.) Government agencies. This includes federal agencies like the Federal Bureau of Investigation (FBI) and the National Security Agency (NSA), as well as local-level agencies like the police department.

Normally, before a wiretap can be placed by any agency, a court order must be issued by a judge who must conclude, based on an affidavit submitted by the government, that there is probable cause to believe that a crime has been, is being, or is about to be committed.

This authority is used to prevent as well as punish crimes. That is, the government can wiretap in advance of a crime being carried out, where the wiretap is used to identify planning and conspiratorial activities. It has been reported that judges almost never deny government requests for wiretap orders.

Government agencies are able to place roaming wiretaps without warrant under the Patriot Act. This essentially allows for a brief period of wiretaps without warrant. Sounds crazy, right? Well, it's true.

3.) Third party persons. This is anyone that accidentally or knowingly seeks to eavesdrop on your communications. This includes family, friends, employers, and prospective thieves. If the third party is not part of the conversation (neither sender nor intended recipient), then they cannot eavesdrop on a communication.

Laws regarding second party (one of the people talking on the phone) call recording or tapping consent vary from state to state. In some states, the tapping or recording party must get consent from the other person on the phone. In some states, you can record or tap without the other person's knowledge.

There is a very important link here, because laws differ between states:

The Technology:

Radio Taps:

Radio taps include the traditional "bug" seen in the movies that fits on a telephone line: on the phone inside the house or outside on the phone line. It may produce noise (a slight signal feedback on the monitored line due to poorly made equipment). These devices tend to be low-powered because the drain on the line would become too great. As a result, the receiver is usually located within a radius of 1 mile (You know... in the movies, with the detectives sitting outside in a van eating donuts). Law agencies do not usually use this technique because they have access via the "telephone exchange " (at the actual telephone company).

Radio Scanners: Specifically a concern for cordless landlines. These devices pick up the full range of wireless transmissions from emergency and law enforcement agencies, aircraft, mobile systems, weather reports, utilities maintenance services, and more.

As a rule of thumb: the newer your wireless phone is, the harder it is to eavesdrop on. The older analog cordless phones can be picked up with something as simple as a baby monitor. Earlier digital phones that only use one channel for transmission can easily be eavesdropped on.

Newer digital cordless phones transmit over multiple channels and often use Digital Spread Spectrum (DSS). DSS typically uses frequency hopping to spread the audio signal over a much wider range of frequencies in a pseudo random way.

Direct Line Taps:

Direct line taps include tapping via the actual "telephone exchange" at the phone company. Another possibility is the splicing or tapping of the subscriber's phone line near the house. The tap can either involve a direct electrical connection to the line using a Butt set, a Beige box (phreaking), or an induction coil. An induction coil is typically placed underneath the base of a telephone or on the back of a telephone handset to pick up the signal inductively. Direct taps sometimes require regular maintenance—either to change tapes or replace batteries—which decrease their utility.

Speaker Taps:

Anywhere there is a speaker (active or inactive), a tap can be set up by using amplification devices to transmit a conversation. This includes speakers on answering machines as well as those on cell phones.

Did you know?: That up until fairly recently, cell phones were not allowed in any top secret government meetings because of speaker tapping possibilities.

Recording the conversation:

The traditional way: 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.

Much more common now-a-days and increasingly popular is recording software. Typically these devices link the phone up to the computer and save the conversation as a sound file. Many journalists use this technique in their profession.

Did you know?: Under United States federal law and many state laws there is nothing illegal about one of the parties recording the conversation or giving permission for calls to be recorded without the other person's knowledge.

In public:

Don't forget about traditional eavesdropping techniques like lip reading if you're discussing information you consider to be extremely private.

Eavesdropping at work:

A recent study from the American Management Association (AMA ) found:

"The number of employers who monitor the amount of time employees spend on the phone and track the numbers called has jumped to 51%, up from 9% in 2001. The percentage of companies that tape phone conversations has also grown in the past four years. Far fewer employers monitor employees' voice mail messages, with 15% reporting that they tape or review voice mail. Employers are notifying employees that their phone conversations are being monitored. Of those organizations that engage in monitoring and surveillance activities, 78% notify employees when they monitor time spent and numbers called; 86% alert employees when their conversations are being taped; and among the 15% who tape and review voice mail, 76% notify employees that they are monitoring. To help manage employees' telephone use, employers apply a combination of policy and discipline."

So, in reality there is a good chance that you are being fairly closely-monitored while you are at work. The good news is that your employer most likely notified you of the surveillance techniques they do use.

Know your rights

Telecom Privacy Laws:

Title 18. Crimes and criminal procedure Part I—Crimes Chapter 119-Wire and Electronic Communications Interception and Interception of Oral Communications:

"one has a right of privacy for contents of telephone conversations, telegraph messages, or electronic data by wire." 18 USC § 2510 et seq.

Title 47. Unauthorized Publication or Use of Communications:

"one has a right of privacy for contents of radio messages." 47 USC §605

Wiretapping Laws:

(1) The Federal Wiretap Act, sometimes referred to as Title III, was adopted in 1968 and expanded in 1986. It sets procedures for court authorization of real-time surveillance of all kinds of electronic communications, including voice, e-mail, fax, and Internet, in criminal investigations. It normally requires, before a wiretap can commence, a court order issued by a judge who must conclude, based on an affidavit submitted by the government, that there is probable cause to believe that a crime has been, is being, or is about to be committed. Terrorist bombings, hijackings and other violent activities are crimes for which wiretaps can be ordered. (The PATRIOT Act expanded the list of criminal statutes for which wiretaps can be ordered.) This authority is used to prevent as well as punish crimes: government can wiretap in advance of a crime being carried out, where the wiretap is used to identify planning and conspiratorial activities. Judges almost never deny government requests for wiretap orders.

(2) The Foreign Intelligence Surveillance Act of 1978 allows wiretapping of aliens and citizens in the US based on a finding of probable cause to believe that the target is a member of a foreign terrorist group or an agent of a foreign power. For US citizens and permanent resident aliens, there must also be probable cause to believe that the person is engaged in activities that "may" involve a criminal violation.

(3) The Patriot Act – Allows for "roaming" taps. Under Title III, the government has "roving tap" authority, meaning that it can get a court order that does not name a specific telephone line or e-mail account but allows the government to tap any phone line, cell phone, or Internet account that a suspect uses. This authority was initially adopted in 1986 and was substantially broadened in 1999. The PATRIOT Act added roving tap authority to FISA. Roving taps are relatively rare.

The National Security Agency can wiretap and seize records without warrant Patriot Act (Title II, Sections 200, 202, 206, 209) for lawful processes.

  • 200- Authority to intercept wire, oral, and electronic communications relating to terrorism.
  • 202- Authority to intercept wire, oral, and electronic communications relating to computer fraud and abuse offenses.
  • 206- Roving surveillance authority under The Foreign Intelligence Surveillance Act of 1978.
  • 209- Seizure of voice-mail messages pursuant to warrants.

(4) U.S. security agencies and the police can tap with cooperation from the phone company under Communications Assistance for Law Enforcement Act 1994 (CALEA).

Important: State Second & Third Party Laws at:


  1. If you are concerned with phone tapping, your phone should be regularly inspected for new joints, or small wires connected to the line.
  2. Update your cordless phone. Buy a phone that operates on multiple channels and read into the security features.
  3. Minimize private conversations in public places.
  4. Don't forget that if multiple phones exist connecting to the same line, a functional tap already exists.
  5. Be cognizant of who you're speaking to on the phone and consider if they would allow eavesdropping for any reason.
  6. Listing for EM "feedback" while on the phone. It is a sign of cheap tapping equipment.

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December 15, 2008 at 9:58 AM


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