The Newcastle-under-Lyme by-election of 14 June 1842 was caused by the voiding of the election in 1841 of the Liberal John Quincey Harris, on the grounds of bribery by his agents. Mr. Harris, who had not been proved personally cognisant of the bribery, offered himself for reelection against the Conservative candidate John Campbell Colquhoun. The Conservatives publicly proclaimed before the poll their case the Mr Harris was barred from re-standing.