HELP NEEDED IN HOLLAND

Recently a friend from Holland was denied entry to the US and was "deported" on the day of his arrival at JFK. The grounds for this decision rests upon an open bench warrant in my friend's name, dating from 1979, regarding a missed court date to plead to a charge of unspecified petit larceny issued by the NYPD. To complicate matters, my friend was at that earlier time a holder of a Green Card, which he subsequently abandoned (though not formally surrendered) upon his move back to Holland in the mid-80s. His legal residence in the US had not been NYC, so if he was indeed arrested there, it was in passing on his way from Boston to Pittsburgh (or vice verse) where in both places over the years he was a student. Since his relocation to Holland he has visited the US more than several times with no problem, until this impasse presented itself. He has no recollection of the charge or of any incident resulting in such a charge; nor does the case docket number with which he was provided at JFK yield any pertinent information, though the number has been duly traced and confirmed through the NYPD archives. What course of action might you suggest to resolve this matter, working on either shore or both? Many thanks.