This applies to when the family locator app is not installed on the phone (which isn't an option for all of the current iPhone's).
I've found that if you turn off location services on a phone, family locator will continue to show that phone's location as being where it was when you turned the location services off. But worse - it will say that this is your device's location AS OF THE CURRENT TIME. It's bad enough that it doesn't tell you that it couldn't actually get location information for the phone, but it's inexcusable that it will say that this location information is current.
Is there any way to get family locator to tell you that it couldn't actually locate the phone and that the location shown is based on location information from the actual date/time the phone was there?