Republican vice presidential candidate, Indiana Gov. Mike Pence reacts following a campaign rally, Friday, Sept. 30, 2016, in Fort Wayne, Ind. Darron Cummings/AP , the man that President-Elect Donald Trump selected to serve as his vice president, is not without controversy himself.

Pence is considered a far-right conservative by many political insiders.

He even challenged John Boehner for his leadership position in Congress in the past because Pence didn't believe Boehner was conservative enough.

On several issues, Pence has rocked the boat with controversy, ranging from gay rights, abortion, and even cigarette smoking.

Marriage equality and "societal collapse"

It's no secret that Pence stands against expanding rights for gay and lesbian couples. But his distaste for marriage equality goes even further. While he was in Congress arguing against marriage equality, Pence stated that being gay was a choice, and that "societal collapse was always brought about following an advent of the deterioration of marriage and family." In short, Pence said that gay and lesbians being able to marry one another would lead to disastrous outcomes in society.

Pence doesn't think cigarette smoking kills

As late as the year 2000, Pence denied that smoking could kill you. "Despite the hysteria from the political class and the media, smoking doesn't kill," he wrote in an op-ed at the time.

Scientists have long known that smoking damages your body, leading to deathin many cases. Surgeon General Dr. Luther Terry even wrote as much more than fifty years before Pence's op-ed. Yet it took politicians decades before they acted on the information, relying upon Big Tobacco's data (and donations) instead when making policy decisions. Many political leaders, even to this day, still receive big dollar donations from tobacco companies — including Pence, who has reportedly received hundreds of thousands of dollars from them.

Against transgender rights

Pence's views on transgender Americans shouldn't be all-too surprising either, given his already controversial views on marriage equality. Yet that doesn't make them any less alarming. Pence was an early opponent of President Barack Obama's directive mandating that schools allow transgender students to use the restrooms that they identify with. Pence has also indicated that he and President-elect Trump intend to "resolve" the order once they're in office.

Republican U.S. presidential candidate Donald Trump (R) applauds and Indiana Governor Mike Pence waves as Pence's daughter Charlotte looks on at a press event held to introduce Pence as Trump's running mate in New York, U.S., July 16, 2016. REUTERS/Eduardo Munoz

Wanted to defund HIV/AIDs funding in favor of "conversion therapy"

Pence's words on LGBTQ issues are controversial enough on their own, but some of his proposals have frightened many within the community as well. During his first run for Congress, Pence suggested that federal money used to fund research on HIV/AIDS should instead be diverted to programs that "provide assistance to those seeking to change their sexual behavior."

So-called "conversion therapy" is a controversial procedure that attempts to change the sexual preferences of gay and lesbian individuals. It is a practice that has been called out by the American Psychological Association as having no basis in medical fact, adding there is "insufficient evidence to support the use of psychological interventions to change sexual orientation." Several states have already moved to ban the practice.

Opposed repealing "Don't ask, don't tell"

During Bill Clinton's presidency, a policy of allowing gay soldiers to serve in the military was implemented. The popular name of the policy, "don't ask, don't tell," referenced the way in which gay and lesbian soldiers would be acclimated — as long as they didn't say anything, gays and lesbians would be allowed to serve.

In the years following, it became clear that the policy was an unfair practice, a separate-but-unequal way of dealing with the issue. President Obama signed legislation repealing the practice in 2011, but it didn't come about without its detractors, and once again Pence had something to say.

In 2010, before "don't ask, don't tell" was ended, Pence warned that Obama should keep the policy in place. Pence said the policy had been "a successful compromise" since the 1990s, and that we shouldn't risk the readiness or recruitment of our military in "an effort to advance some liberal domestic social agenda."

Mike Pence. Jeff Swensen/Getty Images

No women in the military, either

Pence isn't just against gays and lesbians serving openly in the armed forces — he's also been critical of women serving. In the late 90s, before he was in Congress, Pence argued that "the hard truth of our experiment with gender integration [in the military] is that is has been an almost complete disaster for the military and for many of the individual women involved."

He even challenged institutions for suggesting otherwise, including some pretty harsh criticism aimed at Disney's animated feature Mulan. "I suspect that some mischievous liberal at Disney assumes that Mulan's story will cause a quiet change in the next generation's attitude about women in combat," he wrote, "and they just might be right."

Fought against Planned Parenthood and reproductive rights

Most conservative leaders are against any funding to Planned Parenthood, the organization that aims to assist men and women across the country with reproductive health services, including abortion. But Pence took it to another level entirely.

When Republicans took back Congress after the 2010 Tea Party wave, Congressman Pence authored a bill to defund Planned Parenthood, completely removing all federal funding from the group. Pence was even willing to take extreme measures in getting it passed. When asked if he'd be go as far as to shut down government over it, Pence responded in the affirmative: "Of course I am."

Indiana Gov. Mike Pence (R). Reuters/Sean Gardner

Tried to redefine rape

In another attempt to make abortion less accessible, Pence authored a law that tried to limit how and when federal funds for the practice could be used. Under federal law, the only exceptions for which abortion can be performed with federal funds is in case of rape or incest. So Pence attempted to change the definition of rape to include only what he described as "forcible rape."

That definition meant that federal dollars couldn't fund abortions in other instances of rape (for example, where a victim is drugged). Many called Pence out for this action, and the measure was later dropped.

Religious Freedom Restoration Act

Mike Pence gained notoriety in 2015 for signing the Religious Freedom Restoration Act into law. The law made it possible for businesses within the state of Indiana to discriminate against members of the LGBTQ community based on their personal religious beliefs.

Pence did his best to label the law as defending religious freedom. "The Constitution of the United States and the Indiana Constitution both provide strong recognition of the freedom of religion but today, many people of faith feel their religious liberty is under attack by government action," Pence said when he signed the bill.

But detractors weren't convinced. The law brought calls for boycotts on products from Indiana, and continues to be a problem for the state today.