During an interview with CNN's Chris Cuomo, the two discussed same-gender marriage. Even though the Supreme Court is expected to decide this summer whether all 50 states are obligated to allow same-gender marriage, Carson said the issue should be decided at the state level.
"What if people of a state vote for a law, 100-0, that winds up infringing on the rights of a minority?" asked Cuomo. "Like happened very often with slavery, and like many would argue is happening now with people who are gay."
Carson did not see that as a valid comparison, saying, "People have no control over their race."
"Do you think they have control over their sexuality?" Cuomo asked him.
"Absolutely," Carson responded. Cuomo then asked the direct question, "You think being gay is a choice?"
"Absolutely," Carson said.
Carson used the prison system to justify his position.
"A lot of people who go into prison go into prison straight—and when they come out, they're gay," he said. "So did something happen while they were in there? Ask yourself that question."
Watch the exchange here:
The majority of the medical community and the American Psychological Association actually believe "most people experience little or no sense of choice about their sexual orientation."
Carson also said he thinks same-gender couples should not be allowed to marry (a position he has made before), but should have the same legal rights as heterosexual couples.
"Why can't any two human beings, I don't care what their sexual orientation is, why can't they have the legal right to do those things?" he said during the interview. "That does not require changing the definition of marriage."
On Thursday, Carson apologized for his statements. "I realized that my choice of language does not reflect fully my heart on gay issues," he said. "I do not pretend to know how every individual came to their sexual orientation. I regret that my words to express that concept were hurtful and divisive. For that I apologize unreservedly to all that were offended."
He also criticized CNN for airing the comments and said he would not address the issue any more during his campaign.
Not the First Time
Dr. Carson, a former FOX News correspondent, is known for making questionable comments.
In January, during a Republican National Committee meeting, he compared ISIS to Revolutionary War soldiers who battled the British.
"A bunch of rag-tag militiamen defeated the most powerful and professional military force on the planet. Why? Because they believed in what they were doing. They were willing to die for what they believed in. Fast forward to today. What do we have? You've got ISIS. They've got the wrong philosophy, but they're willing to die for it while we are busily giving away every belief and every value for the sake of political correctness. We have to change that."
In a CNN interview last year, Carson stood by his comments made in March comparing the U.S. to Nazi Germany. In an interview with conservative news outlet Breitbart.com, he said the Third Reich was "using its tools to intimidate the population" and that "we now live in a society where people are afraid to say what they actually believe."
He suggested during the interview that the U.S. government "is using instruments of government, like the IRS, to punish its opponents."
He has also compared the Affordable Care Act to slavery.
On Tuesday in a video, Carson announced the formation of an exploratory committee for a 2016 Presidential run.
"If I run for President, it will be because I know what it's like to grow up in a tough neighborhood and feel marginalized," said Carson, who grew up in inner city Detroit.
An NBC/Marist poll last month showed him winning the support of 10 percent of South Carolina Republican primary voters.
In the straw poll of attendees at the CPAC conservative conference near Washington D.C., Carson placed fourth.