While an IP address is not an identity, it can still zero in on a location. I suspect governments and ISPs all keep historical logs of who was assigned what address.
An IP address in itself is not an identity, but it can be easily resolved to one. This is why IP address are considered PII, and are handled like such by any competent security organization.
Do you have any source to back that up? Last I heard a random person or company won't have a way to find out the real identity given just an IP in general.
Per multiple opinions I got from people whose job was to advise me on the matter, a 2016 ECJ ruling[0] suggests that it doesn't matter if a provider can find a person from their IP address or any other detail, but that there exists a scenario where it is possible.
I am not sure how the CCPA treats IP address, but unless you're at Google or Facebook, it doesn't matter. Few can afford to build separately for the EU and the rest of the world, and hence err on adapting the strictest interpretation.
But the threat actor in this case is a state, which does have that ability. (And data brokers of varying degrees of shadiness can and do provide this info to anyone for a price.)
You may need a bit more than that. Especially for shared IPs or when using CGNAT as you need which IP and Port-range was used and during what time-range.
It can be used to identify a location, but not an individual.
I assume it could be easily challenged in court (network was compromised, “i give out my WiFi to anyone who visits my home”) without other supporting evidence.
Not in Germany, where you are responsible for the Wifi access, see hundreds of copyrights fines each year...
Anyway, it puts the persons living in that location on the radar of the police, and other evidence can be collected (For example by getting a warrant and taking all electronics out of the "location").
Apparently in Germany you can do public wifi now, but you have to register as a telecommunications provider, and comply with all law enforcement requests to wiretap your wifi.
