Ignorance of law is not reasonable justification for negating driver responsibility. Driver seeing sign behind a truck- police assume not seeing sign is just an excuse. Presence of passion is also not a good excuse for escaping responsibility. If heart attack or stroke happen, the driver has no responsibility. Habit does not free drivers from legal responsibility.
People act more on social responsibility than to legal ones.
One example is if a Doctor is rushing to aid sick child at 7 am on an empty street. The appeal was lost. If lawmakers make speed limits at 30 mph and there are children and parked cars, drivers are expected to slow down. If motorists engage in unlawful driving, it's probably not all the time, doesn't mean a defect in responsibility, but negation of legal responsibility for the sake of a social one. I would move one lane over to the right.