Step 1.
If the address located in unincorporated land,
land belongs to no city, county owned.
The question is, what city name would the address use?
Let's find out
Step 2.
from here, you can find a handful unincorporated land
https://transparentgov.net/json2tree/gateway/google/hover.html?layer_id=0&url=https%3A%2F%2Fservices.arcgis.com%2FRmCCgQtiZLDCtblq%2Farcgis%2Frest%2Fservices%2FCounty_City%2FFeatureServer&layer=County_City&panto=0¢er_lat=33.91933347673819¢er_long=-118.24080059516766¢er_zoom=12

Step 3.

Step 4.

Step 5.
model I use is here
https://transparentgov.net/json2tree/esri/server/folder.html?org=https%3A%2F%2Fservices.arcgis.com%2FRmCCgQtiZLDCtblq%2Farcgis%2Frest%2Fservices&url=https%3A%2F%2Fservices.arcgis.com%2FRmCCgQtiZLDCtblq%2Farcgis%2Frest%2Fservices&arcgis_online_token=&timeout=9000&select_folder=703&select_folder_text=County_City+%3Csup%3EFeatureServer%3C%2Fsup%3E&select_layer=0&select_layer_text=0+%26%23x21E2%3B+County_City+%3Csup%3EFeature+Layer%3Csub%3E+esriGeometryPolygon%3C%2Fsub%3E%3C%2Fsup%3E

Step 6.
click map to show address use this model

Step 7.
This is unincorporated county land,
just use nearby city name in their address
The city name in address is not always true.

Step 8.
This is unincorporated county land,
just use nearby city name in their address
The city name in address is not always true.

Step 9.
This is unincorporated county land,
just use nearby city name in their address
The city name in address is not always true.

Step 10.
conclusion:
unincorporated county land, just use nearby city name in their address.
In this sample:
green and purple both are unincorporated county land,
but green are use Los angeles in their address, see previous sample
Purple are use huntington park in their address, see previous sample.
Even their address use los angeles, or huntington park,
But, neither LA city or huntington park police officer should deal with this area.
Los angelse county sheriff should deal with green and purple.

Step 11.
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