He sat in the Irish House of Commons for Newtown Limavady from 1765 to 1768, for Clogher from 1768 to 1776, for Ballyshannon from 1776 to 1783, for Newtown Limavady again from 1783 to 1795 and for County Antrim from 1796 to 1800, and then for Antrim in the new United Kingdom House of Commons from 1801 to 1802. John Staples married twice and also had thirteen children. William Conolly Staples (died unmarried in 1798).
Henrietta Margaret (1770–1847), who married Richard Le Poer Trench, 2nd Earl of Clancarty.
Frances, who married Richard Ponsonby,
Grace Louisa (died 1860), who married James Butler, 1st Marquess of Ormonde, and
Catherine (died 1830), who married the Venerable (of an Archdeacon) Robert Alexander and was the mother of Nathaniel Alexander.
Richard Staples (died 1819)
Charlotte Melosina (died 1847), who married William Lenox-Conyngham of Springhill House, Company Londonderry;
Sir Thomas Staples, 9th Baronet (1775–1865);
John Molesworth Staples (1776–1859), father of Sir Nathaniel Alexander Staples, 10th Baronet.