Before the Act of Union 1707, the barons of the constabulary of Haddington (now called East Lothian) elected commissioners to represent them in the unicameral Parliament of Scotland and in the Convention of Estates. The number of commissioners was increased from two to four in 1690.

After 1708, Haddingtonshire returned one member to the House of Commons of Great Britain and later to the House of Commons of the United Kingdom.

List of commissioners

1593 parliament and convention: — Hepburn, laird of WaughtonFoster, p. 178. 1594 parliament and convention: — Hepburn, laird of Waughton 1598 convention: — Hepburn, laird of Waughton 1599 convention: — Hepburn, laird of Waughton 1605: Sir Archibald Douglas of WhittingehameFoster, p. 99.G. Harvey Johnston, The Heraldry of the Douglases (1907) p. 68. 1605: William Douglas of WhittingehameFoster, p. 102. 1605 parliament and convention: — Hepburn, laird of Waughton 1607: Sir Archibald Douglas of Whittingehame 1608: Sir Archibald Douglas of Whittingehame 1609 convention: — Hepburn, laird of Waughton 1612: Sir James Douglas of SpottFoster, p. 101. 1612: Sir Alexander Hamilton of InnerwickFoster, p. 169. 1617 parliament and convention: Sir John Home of North BerwickFoster, p. 182. 1617 parliament and convention: Sir William SetonFoster, p. 312. 1621: Sir Robert Hepburn 1622: John Hamilton of PrestonFoster, p. 170. 1625 convention: Archibald Acheson of GosfordFoster, p. 4.George Edward Cokayne, The Complete Baronetage, volume II (1902) p. 334. 1625 convention: Sir John SetonFoster, p. 311. 1628–1633: John Hamilton of Preston 1628–1633: Sir Patrick Murray of ElibankFoster, p. 270. 1630 convention: Sir Robert Richardson of PencaitlandFoster, p. 295. 1639–1641: Sir John Hamilton of Preston 1639–1641: Sir Patrick Hepburn of Waughton 1640–1641: Sir Patrick Murray of Elibank 1643–1644 convention: Sir Adam Hepburn of Humbie 1643–1644 convention: Sir Patrick Hepburn of Waughton 1644–1645: Sir John St Clair of HermistounFoster, p. 315. 1644–1647: — Cockburn, laird of Clerkington (possibly son of Sir Richard Cockburn of Clerkington)Foster, p. 73. 1644–1647: Sir William Scott of ClerkingtounFoster, p. 308. 1645–1647: Sir John Hamilton of BielFoster, p. 171. 1648: Sir Adam Hepburn of Humbie 1648: Sir William Scott of Clerkingtoun 1648–1649: John Cockburn of OrmistonFoster, p. 74. 1649–1651: Robert Hepburn of KeithFoster, p. 179. 1650: John Hepburn of Waughton 1650: Sir Alexander Hope of GrantounFoster, p. 184. 1650–1651: Sir Adam Hepburn of Humbie 1661–1663: Sir Thomas Hamilton of PrestonFoster, p. 173. 1661–1663: Sir Peter Wedderburn of Gosford 1665 convention: Sir Thomas Hamilton of Preston 1665 convention: Sir Peter Wedderburn of Gosford 1667 convention: Sir Thomas Hamilton of Preston 1667 convention: Sir Peter Wedderburn of Gosford 1669–1674: Sir James Hay of LinplumFoster, p. 175.Complete Baronetage, vol. IV (1904) p. 260. 1669–1674: Sir Peter Wedderburn of Gosford 1669–1674: John Hay, sheriff-deputeFoster, p. 176. 1678 convention: Adam Cockburn of Ormiston 1678 convention: James Fletcher of SaltonFoster, p. 138. 1681–1682: Adam Cockburn of Ormiston 1681–1682: Andrew Fletcher of SaltounFoster, p. 137. 1685–1686: Sir John Lauder of FountainhallFoster, p. 208.Complete Baronetage, vol. IV, p. 361. 1685–1686: John Wedderburn of GosfordFoster, p. 354. 1689 convention: Adam Cockburn of Ormiston 1689 convention: Sir Robert Sinclair of StevenstonFoster, p. 317. 1689–1692: Adam Cockburn of Ormiston (vacated on appointment as Lord Justice Clerk, 28 November 1692) 1689–1702: Sir Robert Sinclair of Stevenston 1690–1702: Sir John Lauder of Fountainhall 1690–1702: William Morison of PrestongrangeFoster, p. 258. 1693–1702: William Hepburn of Beinstoun 1702–1707: Andrew Fletcher of Saltoun 1702–1707: John Cockburn, younger of OrmistonFoster, p. 75. 1702–1707: Sir John Lauder of Fountainhall 1702–1707: William Nisbet of DirletonFoster, p. 275. In February 1707, Cockburn and Nisbet were elected by the other shire commissioners to serve among the Scottish representatives to the first Parliament of Great Britain.Scotland in The History of Parliament Online. Accessed 9 April 2014.

References Joseph Foster, Members of Parliament, Scotland (2nd edition, 1882)