@matchboxbananasynergy and I were having a bit of discussion on Reddit regarding wireless carrier sharing of data.
Topic spawned from discussion on essentially two classes of data access - Mobile Ad ID (MAID) and Apps collecting behavioral and location information freely available to anyone that wants to purchase the data sets - and - cellular network provider data including Call Detail Records (CDR), SMS, and network triangulation/location that requires a search warrant/court order.
This I was able to find that might be of interest: FBI's Internal Guide for Getting Data from AT&T, T-Mobile, Verizon
Net-net is in order to get cellular network triangulation, call detail records (CDR), and SMS logs, Police and Agencies are required to have a search warrant to pull from your cellular carrier. Obviously the cellular network operator knows within a few meters where each and every IMEI is on their network.
Great thing is GrapheneOS, if used well, can essentially eliminate the Google/Apple/Apps data collection which is sold continually to anyone who wants to buy it. No search warrant/wiretap required, just a few $'s.