In a recent court decision, VPR Internationale v. Does 1-1017 (C.D. Ill.), the court found that IP addresses do not equate to a person.
There is no real way to prove any connection between an IP address and a person, but—at best—only a physical location to which the IP address is attached. From there it must be shown that there is a specific device at the location and a specific person using the device to prove any misdeed.
This is a high burden but a fair one.
Because of technologies such as network address translation (NAT), any number of people can share an Internet connection. Because of Wi-Fi, someone could be using that Internet connection who is outside of the home.
In the case, Judge Baker cited to a similar matter of a raid of a home where someone had downloaded child pornography at the place where the IP address resolved. The home was raided and no such matter was found. It was a neighbor who was using an available Wi-Fi network to cover his tracks.