evidence: Asked about the allegations, Joe Biden told a reporter it was a "smear campaign". No criminal activity has been proven, and no evidence has emerged that Mr Biden did anything to intentionally benefit his son. [...] Mr Bobulinski, who is reportedly a US Navy veteran, separately told Fox News' Tucker Carlson that he had met on two occasions with Joe Biden to discuss business deals with China, the first time in May 2017 when Barack Obama's former vice-president was a private citizen.