After a party, a driver was involved in a single vehicle accident and suffered a blow to the head. The driver has foggy memories of being at the emergency room. Although the driver has fully recovered, he is worried that he might be charged with DUI, because the police responded to the accident, and he had a lot to drink before the accident. However, he was unconscious at the accident scene so there were no roadside sobriety tests, he was not ticketed at the hospital and was never in a police station for a breath test. Could he still be charged with DUI?