AlbanyOfficials at one of the state's largest public labor unions shielded a downstate council leader from potential prosecution after she allegedly used a union debit card to make at least $20,000 in questionable purchases — including liquor, restaurant bills and home improvement items.Several people familiar with the matter, and internal documents filed with the Albany-based Public Employees Federation, indicate PEF's leaders asked to handle the matter as an internal "ethics violation" when contacted several months ago by the office of Rockland County District Attorney Thomas P.