In Pennsylvania, driving under the influence is a crime that is taken very seriously. If you are arrested for a DUI for a second time, you will face harsher penalties than if it was your first. In order for a DUI to be considered your second offense, it must be the second DUI you have been convicted of in the last ten years. After ten years, a DUI is no longer considered for the purpose of grading a following offense. vehicular homicide dui Pennsylvania uses three different tiers to categorize second offense DUI offenders. These tiers are known as general impairment, high impairment, and highest impairment.