For the commonwealth to convict a defendant of aggravated assault, the following elements must be proven beyond a reasonable doubt:
First, the Commonwealth must show that the defendant attempted to cause serious bodily injury to the victim. Serious bodily injured in Pennsylvania means injury that would create a substantial risk of death, or that would cause serious, permanent disfigurement, or protracted loss or impairment of the function of any bodily member or organ. Where the line stands in Pennsylvania with respect to what constitutes serious bodily injury rests with the court. Obviously, the defense lawyer is going to argue, except in the most severe of circumstances, that the injury is not serious as defined by Pennsylvania statute. To find the defendant guilty of aggravated assault, a jury or judge sitting as the arbiter, must find the defendant took a substantial step towards causing the bodily injury.
Second, the defendant’s conduct must be intentional. For example, if a bus driver crashes into a pedestrian while traveling on a windy road, the state may have difficulty proving intent. To be convicted of aggravated assault, the defendant must have had the conscious objective to bring about serious bodily injury. Thus, an accident without intent is not aggravated assault.
Finally, it’s definitely worth noting that the alleged victim need not suffer any injury for the defendant to be convicted of aggravated assault. The greater issue is whether defendant had conscious intent to cause serious bodily injury as defined by PA statute and relevant case law.
Remember that intent by itself is not enough to prove aggravated assault. There must be serious bodily injury. For example, the defense may argue that a lesser crime was intended, such as simply to scare the alleged victim or cause less serious bodily injury.
If the aforementioned elements cannot be proven, then the defendant must be found not guilty. As you can see, proving aggravated assault in Pennsylvania is not an easy task. Many of the so called aggravated assaults charged as such by the DA, cannot stand up in court when closely examined by a competent defense lawyer.