What isn't known is how McBride spent the time between the crash and the shooting. Wafer called 911 at 4:42 a.m., but it's not clear when he fired the fatal shot.
"We assume she was looking for help," said Thurswell, who also put forward a theory from one of McBride's two sisters, who said a drunken and disoriented McBride may have believed she was knocking on the door of her family's home since both that residence and Wafer's are corner lots.
Bretz said a potential defense argument is that McBride's extreme drunkenness posed a threat.
"Was she acting crazy? If so ... this gave (Wafer) a greater right to be afraid," Bretz said.
The toxicology report also indicated McBride's blood tested positive for the active ingredients in marijuana.
McBride's family said it doesn't matter, but Bretz said he could see the defense focusing attention on McBride's behavior.
"It makes her out not to be an angel. She got drunk and stoned and drove and crashed her car. But that's not a death-penalty offense," he said.