Legal Evidence from Dedicated Computers

The Internet of Things is populating our world with a multitude of embedded devices, SCADA systems and other little computers.  The video below demonstrates a reliable way to record what a little computer displays at a moment in time, so that a legal authority like a jury can evaluate the recording as evidence months or years later.

How to Preserve Audit or Criminal Evidence


For an official investigator, the collection and preservation of evidence from tiny, dedicated computing devices and sensors can be troublesome.  These devices -- which might include for instance the Nest thermostat or a smart-grid power meter mounted on the side of a house – are multiplying like rabbits.

As a professional investigator – such as a police officer or a forensic auditor – encounters one of these Internet-of-Things devices, she may lack a convenient way to tap into it and extract data from it.  Even though the maker of the device may have a tool that can do that, the investigator may not have the time and resources necessary to research the tool, purchase the tool, wait for it to be delivered, learn how to use it and so on.

Further, the circumstances of the investigation may not justify the investigator attempting to confiscate the device and physically remove it to a secure location.  In fact, the process of moving the device may itself damage evidence or inflict undue hardship on people (like the residents of an apartment complex) who rely on the device to function.

However, it is possible the device sports some kind of visual
Digital Readout
display that shows valuable evidence.  This evidence needs to be recorded.  Tomorrow the evidence may vanish.

In some cases, a trustworthy video record of the data presented on the visual display may serve the investigator’s needs.

Video Demonstrates a Legal Affidavit

The video below is simplistic.  It records the functions of a mere calculator (No.  It’s not linked to the Internet).   But the video does teach techniques for memorializing the data presented on a visual display (like the display on an industrial control system) at a unique place and time.

The same techniques could apply to data manifested as sounds coming from a speaker on the device under examination.

The techniques taught in the video above are in keeping with techniques I have been explaining in other contexts, such as:


In the calculator video above, the investigator plays the role of eyewitness.  He sees something, he records what his eyes see, he narrates the recording, and then he puts his reputation behind the recording.  On camera, he says, “I Ben Wright hereby sign and affirm this recording as my official work.”  In effect he creates a legal affidavit to support his fallible memory.

Affidavit Inhibits Misrepresentation


Can he lie?  Yes.  Can he fabricate the data on the video?  Yes.

However, his professional reputation is on the line.  Suppose the investigator creates this video – which includes his voice, his face and his moving lips.  And suppose later a worthy adversary, like a defense lawyer, proves that his video is a fraud.  The investigator can lose his job; he can lose his license; he can lose his professional credentials.

Thus, the affidavit language in the video fosters truthfulness.

Another way to make the video more credible is to corroborate the date and time stated by the investigator with his voice on video.

I Learn from You!


I wish to hear from you, the reader.  Is this video useful to modern audits, inspections and investigations?  If not, please tell me how to improve my techniques.  Please point me to material that does a better job of mining the Internet of Things for credible legal and accounting evidence.