Well speaking from the perspective of someone who works in the profession, while dynamic IP assignment (DHCP) is how probably 90+% of public facing IP addresses are assigned the reality is that it is exceedingly rare for your dynamic IP address to change. For my work I maintain and IPSEC VPN...
It always grinds my goat when I see these events called accidents. There was nothing accidental about them. Someone raised their weapon, aimed, and fired. A deliberate process. This is homicide. Negligent homicide if you give them the benefit of the doubt but homicide nonetheless.