Former British Conservative Party MP Douglas Carswell (R) addresses a press conference in central London on August 28, 2014, with UKIP Party leader Nigel Farage (L). British MP Douglas Carswell dealt a heavy blow to Prime Minister David Cameron on Thursday as he announced he was to leave the Conservative Party and join the UK Independence Party (UKIP).  AFP PHOTO / JUSTIN TALLIS        (Photo credit should read JUSTIN TALLIS/AFP via Getty Images)