Is it legal to trace a call?

Is it legal for a person who receives a telephone call, to trace that phone call? For example, ‘Cardmember Services’ (the ‘Rachel’ or ‘Heather’ or ‘Anne’ calls) displays spoofed numbers on the Caller ID. Is there commercially available software that can be bought, that will trace the call back to its real origin (actual phone number and address)?

Tracing a call is a common device in fiction, where the Heroic Hacker finds the Bad Guy by tracing the call. Can this happen IRL?

Usually, plugging it into Google will yield something for you. For example, I got a robocall the other day from 253-236-2033. I Googled it and got a bunch of hits. Here’s one of them.

I’m talking about spoofed numbers. For example, your phone says 253-236-2033. You search for the number on Google, and you find out it’s a disconnected number or whatever number is displayed has a non-existent area code or something. The number being displayed is spoofed – like when you get spam from your own email address, or when your Log Into Your Bank Account email has a valid Citi Bank address, but when you look at the header the email came from the Russia.

Obviously the phone call was placed from somewhere, and that ‘somewhere’ has a real phone number. Short of being a government agency or phone company investigator, is there any way to find out the real number?

No. All of that connection data is internal to the phone companies involved. Your phone company may be able to provide you with the details of the originating number (if it was a local call) or information on which interconnect the call came in on (for a nonlocal call), but they don’t have to do so unless you demonstrate harassment (and possibly raise a complaint with police). These days it is much easier to recover this data, as it is digital and logged by the phone companies - in the past with electromechanical switch frames, connection data was not recorded, so “tracing a call” was a complex operation that could take some time. This time delay is not necessary now.

Caller ID is a way of passing originator data across networks for user convenience. Caller ID Spoofing allows companies to aggregate multiple individual numbers behind a single phone identity - however, (in my opinion) the phone companies should be taking more care to screen clients capable of using Caller ID Spoofing to prevent abuse.