Former party chairman stands down after revelations he knew about bullying allegations against aide almost a year agoGrant Shapps, the former chairman of the Conservative party, has resigned as a government minister, Downing Street has confirmed, following Guardian revelations that he failed to act over alleged bullying in the party.Writing to the prime minister on Saturday to formally offer his resignation from the position of international development minister, Shapps said the “buck should stop with me” over issues that arose while he was chairman.