Democratic presidential nominee Hillary Clinton claims to uphold religious liberty, but a lot of people have their doubts.

One such person is Georgetown University professor Thomas Farr, who is the director of the Religious Freedom Project at the Berkley Center for Religion, Peace, and World Affairs.

"Anyone who believes that a President Hillary Clinton will support the religious freedom of Catholic elementary and high schools, colleges, refugee services, adoption agencies, homes for the aged poor, or any other private organisation, is making a mistake," Farr told the Catholic News Agency.

"Her own words suggest that even churches will not evade her understanding of the kind of 'compelling government interest' that she considers abortion and same-sex marriage to be," he said.

Clinton talked about upholding religious freedom in a report carried by the Utah newspaper The Deseret News. "As Americans, we hold fast to the belief that everyone has the right to worship however he or she sees fit," she was quoted as saying. "I've been fighting to defend religious freedom for years."

Clinton added that Americans don't always have to agree on everything, but when it comes to religion, people should "strive to be accepting of everyone around us."

Brian Burch, president of CatholicVote.org, also expressed doubts on Clinton's statements. He said the presidential hopeful "favors extremist policies that would punish charities like the Little Sisters of the Poor along with thousands of similar Catholic-inspired charities."

Clinton also noted that she will preserve the "right to worship," but both Burch and Farr don't believe that she will do so once she wins the White House.

"She publicly opposes the long understood definition of religious freedom by hiding behind the euphemism of 'freedom of worship,'" Burch says. "What this means is she supports the freedom of Catholics to pray inside of our churches, at least for now. But once outside we must embrace the orthodoxy of secular anti-Catholic progressives."

As for Farr, he recalled that Clinton said last year during an international conference that religious groups who oppose abortion will have to change. This is why there is no truth to what she is saying now, he said.