Does voice-activated eavesdropping technology listen in on phone conversations for suspicious “keywords”?

Dear Cecil:

Is it true that U.S. and Canadian federal law-enforcement agencies have a voice-activated system connected to local telephone networks that activates and records telephone conversations based on certain keywords? I only ask this because a reliable source told me so. However, I am very skeptical because I can't believe any government agency has the authority, let alone the technology.

Cecil replies:

The technology is the authority, sport. But you’re right to be skeptical. The U.S., UK, Canada, Australia, and New Zealand are said to operate a vast computerized eavesdropping apparatus known as Echelon that automatically scans all electronic communications (telephone, E-mail, fax — you name it) looking for certain keywords — say, bin Laden. Suspect messages are routed to a human analyst for investigation, and next thing you know somebody’s getting a visit from the men in black or, worst case, looking at the business end of a laser-guided bomb.

Is it possible? Up to a point, sure. The U.S. and its allies have long intercepted and, if possible, decoded diplomatic cables. In the 1960s, when cable traffic began to be stored on magnetic media, it was a relatively simple matter to develop computer programs that could decrypt messages en masse and search for keywords, and something of the sort undoubtedly continues today. The question is scale: it’s one thing for government spooks to eavesdrop on some communications; it’s something else to listen to them all.

We know what we know about Echelon because of the efforts of several determined investigative journalists. The most thorough and persuasive account I’ve seen is James Bamford’s recent book Body of Secrets: Anatomy of the Ultra-Secret National Security Agency. The NSA, a shadowy organization with a budget larger than the CIA’s, oversees U.S. electronic eavesdropping, variously known as “sigint” or “comint” (signals/communications intelligence). According to Bamford, following World War II the U.S. and Great Britain agreed to pool their electronic intelligence-gathering efforts, an arrangement that became known as the UKUSA (pronounced yoo-KOO-sah) agreement. Australia, Canada, and New Zealand were invited in later.

Using sophisticated technology at listening posts around the world, the NSA and other participating agencies monitor all manner of international electronic communications, including satellite and land-based radio transmissions, telephone calls, cable traffic, even computer emissions. A massive computer installation at NSA headquarters in Fort Meade, Maryland, winnows the intercepts by looking for messages containing predetermined keywords. Apparently an intelligence “consumer” (a military planner, for example) can type in a set of keywords and have Echelon deliver a digest of all intercepts meeting the desired criteria, much as one might use an Internet search engine.

The targets of NSA monitoring are mostly foreign governments and other parties overseas (e.g., suspected terrorists or companies thought to be selling sensitive technology to the bad guys). The Foreign Intelligence Surveillance Act of 1978 (see prohibits U.S. agencies from spying on American citizens without a court order, but that was written before we all got on the Internet, and some fear the government may take advantage of loopholes to snoop on ordinary folks. Europeans outside the UK are also worried that Echelon will be used to give businesses in UKUSA countries an unfair advantage. One oft-told story is that U.S. officials were able to swing a Saudi aircraft order from Airbus to Boeing by disclosing that the European company was handing out bribes. The European Parliament recently issued an alarmed report about Echelon and sent a delegation to the U.S. to find out more, apparently in vain.

For all its sophistication, there are limits to what Echelon can do. As far as I can tell there’s no voice-activated system connected to local phone networks that records conversations based on keywords. Until recently, says Bamford, voice recognition technology just wasn’t sophisticated enough. Recent advances may make such automated monitoring possible, but the technology hasn’t been widely deployed — most monitoring of voice telephone calls is done the old-fashioned way, by people listening with earphones.

In addition, because of the scale of modern communications, nonmilitary traffic is typically monitored at what might be thought of as pinch points — that is, places where a high volume of messages is funneled through a relatively small number of channels (communications satellites, microwave relay stations, etc). Wholesale eavesdropping on all communications, both foreign and domestic, is almost certainly beyond the NSA’s capabilities. Indeed, the explosive growth of communications over the past ten years (Internet, cell phones, fax machines), coupled with the introduction of seemingly unbreakable encryption, has made it even more difficult for the NSA to keep up. So we’ve got a curious situation: on the one hand, ordinary folks worry that Big Brother is watching, while on the other, the NSA and its fellow agencies fret that, increasingly, they can’t.

More on voice recognition technology

According to ZDNet UK, an online news service (

Patent number 5,937,422 was applied for in 1997 by the US National Security Agency (NSA) and describes a technology as a ‘method of automatically generating a topical description of text by receiving the text containing input words’. It employs machine transcription — ‘a technique for converting speech into text’.

ZDNet also reports (

Voice recognition remains a hotly-debated capability of Echelon. Systems capable of automatically triggering tape recordings on key words have existed for a while, but their reliability, scale and usability have never been established. Some automation is undoubtedly used, but it is unlikely to extend to full transcription of all calls.

Like I said.

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