From Mega McArdle of the Atlantic taking a detailed look at the incidents were highly correlated with three things:
- being elderly,
and parking (or leaving a parking space).
it's a little hard to be sure that some of the cases were sudden acceleration incidents, because the witnesses to what happened in the car were all killed; the family is trying to reconstruct what happened from their knowledge of the deceased. Obviously, most people are going to err on the side of believing that the car was at fault, rather than a beloved relative. Further complicating matters, most of the cases involve either a lawsuit against Toyota, a complainant facing possible criminal charges, or both.
When you look at these incidents all together, it's pretty clear why Toyota didn't investigate this "overwhelming evidence" of a problem: they look a lot like typical cases of driver error. I don't know that all of them are. But I do know that however advanced Toyota's electronics are, they're not yet clever enough to be able to pick on senior citizens.
See the article How Real are the Defects in Toyota's Cars?