We’ll jump to the point here: There is no conclusive evidence to support Carson’s claim that 'a lot of people' make a switch from heterosexual to homosexual while in prison. So, did something happen while they were in there? Ask yourself that question,' said Carson, a former head of pediatric neurosurgery at Johns Hopkins Hospital. 'Because a lot of people who go into prison go into prison straight - and when they come out, they're gay. He also argued that homosexuality is a choice, rather than biological. In a March 4 interview, the likely 2016 presidential contender said he believes that legalizing same-sex marriage is a decision that should be left to the states. Homosexuality is a choice, just look at the prisons, Republican neurosurgeon Ben Carson said on CNN.