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Defining Intelligence Sources

Intelligence gathering has evolved over the years primarily due to technological advances and the ways in which people use technology in their everyday lives. It has both changed and enhanced traditional investigative methods, transforming how investigators conduct surveillance, interviews, and research.

But while we see new approaches to information collection disciplines, the goal remains the same – produce timely, accurate, actionable intelligence. And because intelligence can take many forms and come from many sources, the collection of information, or intelligence gathering, can be further classified by type and activity. Regardless of the genre of intelligence or the method used to obtain it, all intelligence has several common factors; it must be gathered legally to be admissible as evidence or to be used in an investigation. Both the source and the data itself must be evaluated separately to ensure information meets legal, ethical and regulatory standards to be considered intelligence.

Here is an explanation of some of the most commonly-used types of intelligence in private investigations:

Human Intelligence (HUMINT)

Often used in its abbreviated form and pronounced hyoo-mint, human intelligence originates from interpersonal contact with human sources. This form of intelligence gathering typically involves interviews, interrogations, or casual conversations. Prior to approaching an HUMINT gathering operation, the individual(s) who may be in possession of meaningful and relevant HUMINT must be thoroughly background checked to determine their reliability, their motive for providing information (if they are aware), and their ability to access the intelligence being sought. HUMINT gathering may be conducted openly by interviewing witnesses, suspects or willing informants, or covertly via subterfuge or espionage.

Open Source Intelligence (OSINT)

Open Source Intelligence (OSINT) refers to processed information collected from publicly available or “open” sources such as the news media, internet, public databases, professional and academic publications, commercial data, and grey literature.

Both the U.S. Director of National Intelligence and the U.S. Department of Defense (DoD) define OSINT as “publicly available information that is collected, exploited, and disseminated in a timely manner to an appropriate audience for the purpose of addressing a specific intelligence requirement."

The amount of potentially valuable information and incriminating evidence that currently exists on social media, apps, databases and websites is immeasurable, and there is a wealth of data that investigators can collect from these publicly available sources. There are literally thousands of effective tools online that can make the task of collecting, storing, analyzing and disseminating OSINT easier.

Social Media Intelligence (SMI or SOCMINT)

Social Media Intelligence is a subset of OSINT; it is the collection and processing of intelligence from social media sources. As more and more people use social media to casually and openly share the details of their personal and business lives, social media has become an abundant resource for intelligence gatherers.

Where there is publicly available information, there will be people intent on exploiting it for financial or personal gain and such, social media has also become a rich environment for cybercriminals to commit fraud, impersonation and stalking. The majority of investigations now involve an electronic device or the transmission of digital data at some stage, whether as a storage, research or communication means, and investigators must, at the very least, have a working knowledge of this environment if they are to conduct an effective investigation. SOCMINT can be gathered both intrusively or non-intrusively by accessing open and closed social networks, with consideration given to legal constraints and compliance with terms of use provided by the platform or app used.

Signals Intelligence (SIGINT)

Signals Intelligence (SIGINT) involves collecting and analyzing electronic signals (ELINT) and communications (COMINT). The NSA defines SIGINT as “intelligence derived from electronic signals and systems used by foreign targets, such as communications systems, radars, and weapons systems.” SIGINT provides insight into the capabilities and intentions of adversaries.

SIGINT gathering can involve devices that interfere with wireless connections, such as flash drives fitted with radio transmitters, or smartphone malware that can monitor a user’s communications, activities, and locations. As the technology behind SIGINT interception and monitoring becomes more sophisticated, so will the quality and quantity of SIGINT deployment.


Where intelligence gathering used to involve dumpster diving, tailing suspects for days and trawling through filing cabinets and library shelves, we now have unprecedented access to information at our fingertips, anywhere in the world, at any time of the day or night. And because the methods of intelligence gathering are becoming increasingly more accessible to investigators, it is crucial to know what they are, how to access them and how to leverage the data gathered in a legal and ethical way. The types of intelligence mentioned in this article are by no means exhaustive, there are acronyms galore in the intelligence world, however, understanding the basics, and knowing that these really are the basics, is an essential first step in being an effective investigator in the information age.

If you would like more information about intelligence gathering or want to keep up to date on issues important to investigators; follow me on Twitter, Instagram, and LinkedIn, or email me at You can also listen to our weekly discussions on the World-Class Investigator podcast.

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