I'm not so sure about that. Regardless of his intent, his actions were reckless at best. An example can be taken from automobile accidents. A person driving responsibly, obeying the traffic laws and showing due care, would not be held responsible for someone stepping out in front of his car and being killed. A person driving at excessive speed and weaving in and out of traffic probably would. By violating the rules of safe driving he puts others at risk.
The same should apply here. If the shooter had been practicing at a range, for example, and a stray bullet killed someone, chances are it's a tragic accident. But firing a bullet into the air is reckless and a danger to the public. The person responsible should be charged with involuntary manslaughter, at least, and reckless endangerment. And there's a good chance that, even if he manages to avoid jail time, he'll be the subject of a civil suit by the victim's family.