Shadowy Toyota logo with Camry

Last year, Edmunds asked its readership to recreate a mechanical or electrical cause of sudden unintended acceleration of the kind that allegedly plagued Toyota in 2009 and 2010. The prize for coming up with verifiable proof of mechanical failure causing SUA was a cool $1 million dollars. Perhaps unsurprisingly, that contest just concluded without a winner.

Over the course of the year, Edmunds readers were unable to come up with proof that a mechanical or electrical fault caused the accidents that led to Toyota's drastic recall. That backs up NASA's finding that absolved Toyota of any wrongdoing. With mechanical failure ruled out as a viable cause of SUA, we're left with an uncomfortable thought: Short of those dealing with binding floor mats or those sticky recalled pedals, driver error was almost certainly the culprit for the flurry of unintended acceleration claims.