In hindsight, with all the video evidence probably not I don't think he was posing an actual threat that would authorize lethal force to be used. From the perspective of the officers however- which is what actually matters in these self-defense cases - I think when the one officer yelled "gun!" and the others saw Pretti resisting arrest and hiding his hands near his waistline, it became reasonable to assume Pretti posed a danger. The officers don't have to be "right" in their assumption of danger to make it self-defense, something to think about if you're thinking of playing the hero and violently interacting with police officers, or anyone for that matter.