Also see this about injuries
GAO found thirteen studies with data on some aspect of the societal costs of motorcycle accidents.
"These studies indicated that nonhelmeted riders were more likely to (1) need ambulance service, (2) be admitted to a hospital as an inpatient, (3) have higher hospital charges, (4) need neurosurgery and intensive care, (5) need rehabilitation, and (6) be permanently impaired and need long-term care" (GAO, 1991, p. 4)."
Read More