However, the absence of specific error rates is but one factor to consider (See: R v. Beland 1987 CanLII 27 (SCC),  2 S.C.R. 398 at para. 19). In my view, the propagation maps have not lost probative value simply because there is no established confidence level or error rate attached to it. What I take from the evidence is that propagation mapping through the Mentum Planet software is a multi-billion dollar (judicial notice) communication industry’s best effort means (in designing, installing and optimizing cellular towers) to identify, respond to and take advantage of an unchallenged basic general rule of science underlying the relationship of a cell phone tower and a cell phone (i.e. “radio signals will register at the tower with the strongest signal, which is usually, though not always, the closest tower”). And, the maps produced are but demonstrative of the results of that effort. Granted, the design, construction and optimization of cellular networks is not done with forensic cell location evidence in mind. Nonetheless, a cell phone’s general location and the ability to predict a cell phone’s general location relative to a cellular tower based on the “general rule” appears of importance to communication service providers, for obvious quality control and quality assurance purposes. I fail to see how the derivative use for forensic purposes undermines the indicia of reliability associated with the software employed. There is sufficient reliability associated with this type of evidence, worthy of the jury’s consideration.
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