Although I favor privacy and I'm against backdoors, I am not entirely sure how I feel about this. Luckily, Apple says they cannot do it; but, what if they could

Although I favor privacy and I'm against backdoors, I am not entirely sure how I feel about this. Luckily, Apple says they cannot do it; but, what if they could? The individual is dead and there is no question about his guilt. This is not a case of rushing to judgement, like was done with Richard Jewell, In this particular case, if not a terrorist, this guy had issues. Should we be able to access his phone to see what warning signs there were, which might help us identify others with similar issues? If indeed a terrorist and working with others, shouldn't we be able to get information that might help identify those others? How much privacy do you give a dead terrorist/criminal?