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“Learn the step-by-step process of doing a smartphone fire investigation as an engineering expert”

By John D. Gaskell, Retired Consulting Engineer

Author of “The Complete Guide to FORENSIC ENGINEERING

Forensic engineering is defined by the National Academy of Forensic Engineers (NAFE) as “the application of the art and science of engineering in matters which are in, or may possibly relate to, the jurisprudence system, inclusive of alternative dispute resolution.” These engineers serve as consultants to the legal profession and as expert witnesses in courts of law.

Acceptance of Cases

Accept only cases in your field of expertise, but don’t necessarily limit them to your area of specialty. My cases as an electrical engineer included electrocutions, fires of suspected electrical origin, standard of care determinations, equipment failures, arc fault accidents, conveyor accidents, lightning strikes, and others. Yours will be different but also interesting and challenging.


The following is a narrative synopses of one of my cases. This is not intended to be a formal presentation of legal actions. No confidential or privileged information is revealed. This is simply my recollection, intended only to illustrate an expert’s typical involvement in judicial matters.

I was the chief investigator and expert witness on all of the forensic cases of Gaskell Associates, Ltd., and later those of the Gaskell Associates division of Thielsch Engineering, until my retirement. However, it was my practice to meet on each case with my senior staff to “brainstorm” the case. This often opened up avenues of investigation that had not previously occurred to me. I attribute much of my success to hiring others who are smarter than I am.

Case Study – Smartphone Fire

A home was severely damaged by fire allegedly caused when a smartphone was left unattended while charging. The fire marshal and the other fire investigators had identified the origin of the fire to be in the vicinity of the phone. We were hired for the defense by the attorney of the manufacturer of the phone charger. As usual, we read through a lengthy smartphone fire case file, did some research, examined the evidence and an exemplar (new sample of the same item), and visited the scene. We couldn’t find any defect, but we agreed with the information in the case file that the charger seemed to be the only item associated with the origin of the fire with enough energy to start the fire.

Then, somewhat by luck, we came across a news article about lithium-ion batteries catching on fire. We checked the specifications of the phone in question, and, sure enough, it had a lithium-ion battery. These batteries were becoming popular because of their high-density capacity (watt-hours/kilogram). A problem can occur if there is a failure of the thin separators that keep the elements of the battery apart. This can trigger what is known as “thermal runaway,” causing the battery to overheat and burst into flames. Two things that keep today’s lithium-ion batteries relatively safe are improvements in manufacturing techniques and the use of smarter monitoring systems. We also found an article about how these batteries can be damaged by using them in hot environments, causing rapid charging. Two of the depositions indicated that the phone was in front of the window on a carpet in direct sunlight.

Armed with this information, our attorney/client told us to stop all work on the smartphone fire case and to submit our final bill. The lessons here are keep abreast of the news related to your cases and find something else at which to point a finger.

Litigation consulting is interesting, challenging, and profitable. If what is involved interests you, I recommend adding “Forensic Engineering” to your practice as a consulting engineer.

Get Jack’s new book: The “Complete Guide” to FORENSIC ENGINEERING to learn the details. Also, the largest chapter in his book: The “Complete Guide” to CONSULTING ENGINEERING covers the “highlights” of Forensic Engineering. Visit to find out more.

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