Mike Nudelman/Samantha Lee/Business Insider
Many wanted a response from Trump, who had just watched President Barack Obama deliver jokes that night about Trump's constant questioning of the legitimacy of Obama's birth certificate.
Trump now refuses to address his skepticism of the legitimacy of Obama's birth certificate. But it was perhaps the first of numerous debunked or unverified conspiracy theories that Trump has entertained during his time in the political spotlight.
Throughout the 2016 campaign, Trump has floated theories fueled by the conspiratorial-minded corners of supermarket tabloids and the internet, something unprecedented in modern
Critics say it's disturbing, even dangerous, behavior for a presumptive presidential nominee.
"Donald Trump is fueling conspiracy theories out on the campaign trail. Can you imagine that in the Situation Room?" Democratic frontrunner Hillary Clinton's campaign recently tweeted.
Supporters praise him for going beyond the limits of traditional campaigns, and Trump often says he's simply punching back at opponents who are slinging mud at him.
Here are 13 of the most notable conspiracy theories Trump has entertained.