He said generally speaking, most people are not even aware what they are signing up to online and are then "surprised" when the information is accessed.
Private investigators have access to information that some locals are unknowingly sharing when they sign up for certain online services.
Speaking to Kfm, Ian Withers, a well-known private investigator, said the information is reproduced and sold online with data consolidators that some private investigators can then subscribe to.
Mr Withers was instrumental in helping track down paedophile priest Oliver' O Grady.
He also tracked the IRA’s Hyde Park bomber with a bluffed phone call.
He said generally speaking, most people are not even aware what they are signing up to online and are then "surprised" when the information is accessed.
You can listen to the full interview with Ian Withers below.

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