Re: Advice about illegal fireworks
Assuming that the OP lives in a residential neighborhood, there is about a zero chance that the shooter, licensed or not, has been granted a permit to discharge that level of fireworks there. I think this for a number of reasons, starting with the fact that just isn't typically done. Add to that the fact that, when such permits are issued even in an appropriate place, there is usually a requirement to have one of more fire dept, personnel on site as monitors. There may also be a requirement to have apparatus at the site. It would be very unusual for a fire dept. to dilute its resources for someone's private party, on a night when much higher levels of fire service calls are the norm. And, while I don't believe he would have been able to gain fire marshall approval anyway, the 2003 nightclub fire ("The Station") in Rhode Island, in which 100 people lost their lives because someone decided to shoot some 15' gerbs in a room with an 8 foot ceiling, has pretty much assured extremely strict application of rules in regard to fire permits across the country.
I would also be extremely surprised if the neighbor is a licensed shooter simply because I have known a few and they understand clearly the dangers of these devices in the wrong environment. They also tend to be very cautious and don't randomly expose themselves to lawsuits, etc.
If anyone takes the time to look up the fire that I just referenced, they might say that the incident is extreme and not similar to what the neighbor is doing. Yes, The Station fire was extreme in it's result, but the fact of the matter is that a gerb could be somewhat fairly described as an overgrown sparkler. Danielle Biechele, the band manager who used the pyro, certainly didn't set out to burn a nighclub to the ground, kill a hundred people and injure a couple of hundred more in the process. He also didn't think this relatively benign device could do such a thing. But it did because it found a fuel source that wasn't anticipated. The same thing could happen in the OP's neighborhood. All it takes is for one of the rockets to misfire or explode prematurely. A low burst could very easily ignite something that would burn with enough intensity to trigger a chain reaction, igniting other objects, structures and so forth.
If I were "Mr Firecracker's" neighbors, who's homes could be collectively be worth many hundreds of thousands of dollars, his party would be over before it started. I might extend him the courtesy of politely telling him that his intentions were not OK but, beyond that, I wouldn't be nice about it. My position would simply be that I could take or leave his friendship, but that I had a responsibility to myself and my family to protect my home.