Not from the cell phone directly, I imagine. If you have a way to get the phone number, possibly through hacking to nearby bluetooth-capable devices, the nearest of which would be the phone in question, you would work from there. Take the number, and trace it back to the person's name, address, and credit card with which they pay the bill, via hacking into the records of their cell phone service provider. From the credit card company's database, you get the social security number. I'm not sure where the tax fraud info would come from then, but it may involve the IRS and his employer's pay records. Actually, I don't know how to actually go about executing any of the steps I just outlined, but I do believe that would be the logical process by which the information would be obtained. And that would be a very difficult job anyways; he'd have to have some seriously impressive technology on him to manage it that fast on something handheld.