Could an AIDS denialist make it to the White House in 2016? Now that Rand Paul is officially running for president, that question is no longer purely hypothetical. The Libertarian Republican announced his candidacy today, April 7, on his website.

A U.S. Senator from Kentucky, Paul has been known for controversial statements and beliefs. BuzzFeed reports that Paul had been a member of a fringe medical group that questions whether HIV causes AIDS and promotes the idea that vaccinations are linked to autism. Paul had been a member of the group, the Association of American Physicians and Surgeons (AAPS), for more than 20 years.

Although it appears Paul did not renew his membership and it is unclear whether he agreed with all of the AAPS’s statements, he has spoken about the group in public and he is featured in a video on the AAPS website.

The AAPS is against abortion rights and claims it’s “evil” and “immoral” for doctors to participate in Medicare.

The Huffington Post reports that Paul appears in a new documentary titled Light Wins: How to Overcome the Criminalization of Christianity. Featuring a lineup of anti-gay leaders, the film makes the case that LGBT equality is a threat to Christians. In the doc, Paul speaks against marriage equality.

And in a video clip from 2013 that BuzzFeed recently found, Paul says, “I don’t think I’ve ever used the word gay rights, because I don’t really believe in rights based on your behavior.”

Such statements lead one to wonder what this presidential hopeful thinks about the rights and behaviors of people with HIV—and what type of policy and medical research he believes is appropriate to address the epidemic.