IEEE Technology and Society Magazine - December 2016 - 84

corruption plus a second memory corruption (the
throttle angle variable) plus, in many scenarios, yet
a third simultaneous failure (the Brake Echo
Check). Neither theory is satisfied by just a single
memory corruption without at least one other
simultaneous failure.
The expert presented many slides criticizing Toyota's
software quality. See, for example, Slides 11, 14, 23-25,
27-33, 35, 38, 39, 41, 43-48, 50-52. But he did not provide evidence for the occurrence of the specific failures
required by his accident theories.
A second expert also offered testimony criticizing
Toyota's software quality [22]-[24], although he did not
examine Toyota's source code [25], [26]. That expert did
not provide an opinion of his own regarding causation,
nor did he provide an opinion about the first expert's
causation theories [27].

Causation not Demonstrated
The jury was told that "to a reasonable degree of
engineering certainty, it was more likely than not"
that Task X death caused the accident. Two theories
were presented to support this conclusion, but neither theor y was credible. Nonetheless, the jur y
accepted the conclusion.
The message provided to the jury by the plaintiffs
was twofold:
■ The defendant's software was poorly designed and
full of bugs.
■ These bugs likely caused the accident.
As with all non-trivial software, there likely were bugs
in the defendant's software. Perhaps the plaintiffs found
some of them. But this does not mean that the accident
was caused by any of the purported bugs. Causation
was not demonstrated.
Due to the nature of software, it seems likely that
this same scenario will play out in future embedded
software trials. A key to ensuring that an informed decision will be reached by the jury in such a trial is for both
plaintiffs and defendants to adequately address the second bullet point above, causation. Otherwise, the jury
can be convinced that causation has been demonstrated when in fact all that has occurred is that the quality
of the defendant's software has been criticized, perhaps
legitimately and perhaps not. This appears to be what
happened in this trial.

Author Information
The author is with Kelly Computing, Inc., Santa Barbara,
CA. Email: dcummings@kellytechnologygroup.com.

References

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84

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[26] Transcript Of Afternoon Trial Proceedings, Oct. 13, 2013, [23],
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[27] Transcript Of Afternoon Trial Proceedings, Oct. 13, 2013, [23],
pages 80-82, 111.

IEEE Technology and Society Magazine

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DECember 2016

https://www.law.cornell.edu/wex/preponderance http://https:// http://www.justia.com/trials-litigation/evidentiary-standards-burdens-proof/ http://www.nolo.com/legal https://www.justia.com/injury/ https://www.law.cornell.edu/wex/actual_cause https://www.law.cornell.edu/wex/but-for_test https://www.law.cornell.edu/wex/proximate_ http://images.findlaw.com/optimost/accident-injury-law/ http://www.Law.com http://dictionary.law.com/Default http://www.Law.com http://dictionary.law.com/ http://legal-dictionary http://sunnyday.mit.edu/SafetyCases.pdf http://www.scientificamerican http://http:// http://www.pcmag.com/article2/0,2817,1618393,00.asp http://www.ieee.org/ http://www.acm.org/about/se-code http://www.embeddedgurus.com/ http://http:// http://www.latimes.com/news/opinion/opinionla/la-oew-cummings12 http://www http://www.safetyresearch.net/Library/INFD-DP14003-61928.pdf https://www http://www.researchgate.net/publication/266491470_Driver_Braking_ http://www.safetyresearch.net/Library/Koopman%2010-11-13 http://http:// http://www.safetyresearch.net/Library/Koopman%2010-11-13 https://users.ece.cmu https://www.law.cornell.edu/wex/burden_of_proof

Table of Contents for the Digital Edition of IEEE Technology and Society Magazine - December 2016