I know someone who is in jail and his ex-wife has the possession of the car which is registered in his name in the state of NJ and car is paid off. How can he remove his name from title/registration while he is in the jail. He does not have any contact with the ex-wife.
A vehicle can be given as a gift, which avoids sales tax. The procedure is specified here. Remove the plates and return them to a Motor Vehicle agency or Regional Service Center; the owner signs the back of the title and someone fills in new owner's name and address, date of gift, odometer reading, and "GIFT" for sale price. The buyer then signs the back, fills in drivers license number, take this all to MV agency with $60 to transfer title. This needs to be done within 10 business days of the gift date. It is important that the sale price not appear to have been altered, otherwise unspecified "additional information" may be required (to somehow prove that it was gifted, not sold).
And, uh, it is not at all clear what can be done if the plates cannot be returned.