An investigation into how Donald Trump has used conspiracy theories to further his bid for the presidency. If Donald Trump loses his battle to become president, it is already clear that he will blame a conspiracy between the media and the political establishment to rig the election. And it won't be the first time that Donald has pushed conspiracy theories to advance his political career. The latest episode of Conspiracy Files investigates how Trump championed the notorious 'birther' conspiracy - which aimed to prove that America's first black president wasn't eligible to serve, and that his birth certificate was false. It is a claim that was believed by up to 60% of Trump voters - even though Trump has now finally disowned it. To help defeat Ted Cruz during the Republican nomination race, Trump stirred stories about links between Cruz's father and America's most famous conspiracy, the assassination of JFK. And as Trump battles Hilary Clinton, he is focusing relentlessly on allegations that the Clintons have conspired to cover up crimes throughout their political careers. Conspiracy Files probes the murky world of US politics, which, since Watergate, has been fertile breeding ground for increasingly complex conspiracy theories.