The federal government of the United States of America has a rather thorough intelligence machine at its disposal. The various organizations are collectively called the IC (Intelligence Community). The IC itself is led by the Director of National Intelligence and is comprised of 16 organizations or elements.

Examples of some of these elements are:

The Central Intelligence Agency (CIA)

According to CIA official sources the CIA's Director is responsible for duties including:

• "Collecting intelligence through human sources and by other appropriate means, except that he shall have no police, subpoena, or law enforcement powers or internal security functions;"

• "Correlating and evaluating intelligence related to the national security and providing appropriate dissemination of such intelligence;"

• "Providing overall direction for and coordination of the collection of national intelligence outside the United States through human sources by elements of the Intelligence Community authorized to undertake such collection and, in coordination with other departments, agencies, or elements of the United States Government which are authorized to undertake such collection, ensuring that the most effective use is made of resources and that appropriate account is taken of the risks to the United States and those involved in such collection;"

• "Performing such other functions and duties related to intelligence affecting the national security as the President or the Director of National Intelligence may direct."

*From official US government media.

The CIA itself is tasked with assisting the director in the above mission. To accomplish this, the CIA performs research, development and deployment of intelligence technologies. The CIA as an agency is an independent source of analysis and information gathering that works closely with the other members of the IC to ensure the most accurate intelligence possible for all defense, law enforcement and legal bodies that utilize their services legally.

Federal Bureau of Investigation (FBI)

The FBI focuses on threats to not only the nation but the citizens of the United States of America. The Federal Bureau of Investigation protects against terrorist threats and activities, corrupt politicians and dirty officials, foreign and domestic cyber-attacks, transnational and international criminal organizations, criminally insane and extremely dangerous persons, as well as protecting our civil rights from individual and government abuses.

The FBI's Operational Technology Division is the research and development center for the FBI's gadgets and gizmos. The OTD based in Quantico, VA is responsible for creating and supplying the FBI with many of its' cutting edge techniques and surveillance technologies. Most of the work done is far too sensitive for public dissemination, but for the things we know about, it's pretty advanced stuff.

Above and beyond technological advances the OTD is also responsible for most of the forensic media analysis done by the FBI. They also handle the training of FBI agents who need to be briefed in the use of the surveillance equipment and are even deployed on covert missions to install or set up their equipment.

National Security Agency (NSA)

The National Security Agency carries out "The Information Assurance mission" which is purposed with preventing foreign adversaries from accessing sensitive or classified national security information. They also engage in signals intelligence by collecting, processing, and disseminating intelligence based off of foreign signal interception.

Intelligence in the Private Sector - Corporate and Personal Security

The government doesn't have a complete monopoly on surveillance though. There are countless private firms that contract their services out to governments, corporations and individuals for the purposes of providing information and support for defense, legal, and business purposes. These companies may provide forensic services in addition to investigative services to both the public and private sectors.

Equipment and Methods

There are devices that are designed to be covertly installed and monitor an area or room and either record the goings on or broadcast back to a listening post. Some devices attach to phone systems to record calls in either direction. Most intelligence gathering organizations keep their methods a guarded secret and are loathe disclosing exactly what technologies they use.

The telephone companies themselves can attach a device called a pen register to determine and record the number of any phone that is calling on a given line. With digital voice recorders and advances in storage and audio compression some of these devices can record for periods up to 2 weeks or more.

Additionally, more advanced technologies are available such as infrared laser listening devices that can track the vibrations of a window pane and transform the infrared light into an audio stream thereby allowing the operator to listen in on a conversation in a sealed room.

Forensic Audio

Parabolic microphones (for listening from a distance), contact microphones (for listening through walls), covert body recorders, and other field recording devices are designed to pick up speech in exceptional conditions or circumstances. However, while surveillance microphones and recorders make it possible, they often do so at the cost of sound quality.

This is where forensic audio equipment can sometimes be useful. Forensic audio filtering and other techniques can extract a great deal of information from a recording. This can be helpful with identifying a speaker and his marginally intelligible words due to poor recording conditions. However, even with the most sophisticated technology, audio recordings can remain muddy. The recording may remain difficult to understand and possibly even impossible to make out even after a lot of cleanup. For situations like this, forensic transcription and speech decoding can be attempted, although there is still no guarantee that the recording can be deciphered.

Forensic transcription is a tedious process where the examiner uses sophisticated software and hardware to filter and visually examine the speech waveform. Words may also be stretched to make each letter easier to analyze while maintaining the proper pitch so the voice sounds right and not like chipmunks. There are a lot of techniques used but all in all it comes down to an incredible ability to take a noisy mess and extract the words of a speaker.

The Laws of the US

The problem with audio surveillance is that it is 98% illegal. There are only 2 ways to legally record a conversation in the United States. The first way is to inform all parties of the conversation that it is being recorded either verbally or with big obvious signs posted near every microphone which rarely works very well if you are trying to be covert. The other way is by court order, which is not too likely to happen for the average citizen.

There's a vast difference in the technology available for purchase and how audio surveillance can be used by the general public and government agencies. While a civilian may not be able to legally tap a phone or point lasers at their neighbor for the purpose of garnering some gossip, there is some surveillance equipment out there and forensic audio services available for people who find themselves in need of them. It's usually best to consult with an attorney regarding the laws before presenting you audio evidence to the media, law enforcement, or the courts.