Well they don't, and they shouldn't - there simply isn't enough evidence for them to make the right decision, and any judge that allows them to do so by guessing isn't doing justice.
Moreover, the overwhelming majority of cases settle before trial - for criminal defendants, that means a plea bargain and jail or probation. For civil defendants, that means a settlement that could force bankruptcy.
This kind of leave-it-up-to-the-jury thinking is what made Al Gore powerful and John Edwards rich.
You can declare that all a priori for all driving distraction cases? Amazing!
Well they don't, and they shouldn't
You don't believe in juries? Does this tie in with your naturalized status somehow?
any judge that allows them to do so by guessing isn't doing justice.
If I'm not mistaken, it is the role of the defense attorney to point this out.
Still coming up to speed on the American Justice System, are you?