A legal query about right and wrong

Hello all. I have a legal question for you guys. My question is it illegal to use an IP address to find out where someone is at when they are using Facebook to identify the Computer or iPad of a person who is sending the message and then give the message to a third party. To prove or disprove that person is the person who the third-party thinks send the message.

Now the reason I asked this is that I was accused of using someone else's Facebook account. in actuality the person who made the message is the owner of the Facebook account. When my accuser was confronted with this information from the person who owns the account, they refused to believe it . Then a mutual friend decided that they would look into it without consent of all the parties. and look at the IP address in the message log . To prove who's right, or wrong

You see I think it's wrong, because you are trying to pinpoint someone's location, and give this information to a third-party who vaguely knows the person who is being tracked.

Other people have told me that since IP addresses are like ZIP Codes or post codes that it would not be illegal for someone to look up all the IP addresses and match them up to the Facebook account and find out where a person's whereabouts are throughout a city. When I explained that that sounds highly illegal. They said no it's not and they can do it at any time.
Asked Oct 14, 2013

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