Employees of Catholic institutions could lose their jobs if they enter a same-sex marriage in Australia, according to Archbishop Denis Hart, the president of the Australian Bishops’ Conference.

Australians are participating in a postal plebiscite in November, asking whether same-sex marriage should be legalized in the country.

Unlike a referendum, where the citizens’ vote often changes the law or at least cannot be easily dismissed, the plebiscite is only a sampling of public opinion and is not legally binding.

Unlike other elections in Australia, participation by eligible voters in a plebiscite is not compulsory.

Hart, who heads the Melbourne archdiocese, said he was “very emphatic” that Catholic institutions such as schools and parishes exist to teach a Catholic view on marriage.

“We shouldn’t be slipping on that,” he said.

His remarks came in an exclusive interview with Fairfax Media, which owns several of Australia’s leading newspapers.

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“Any words or actions which work contrary to that would be viewed very seriously,” Hart said. “Our teachers, our parish employees are expected totally to uphold the Catholic faith and what we believe about marriage. People have to see in words and in example that our teaching of marriage is underlined.”

However, the archbishop said individual hiring and firing decisions “are best dealt with on the local scene.”

Hart’s concerns were echoed by Perth Archbishop Timothy Costelloe, who chairs the Bishops’ Commission for Catholic Education.

“In accepting a role in a Catholic school, staff will recognize their responsibility to conduct themselves in such a way as not to undermine the fundamental ethos of the school,” Costelloe told Fairfax Media. “Like all other employers, the Catholic Church should be able to ensure its values are upheld by those who choose to work for the organization.”

It is estimated 180,000 Australians work for the Catholic Church and Church-affiliated organizations, constituting about 2 percent of the workforce in the country.

In an August 15 pamphlet on the plebiscite, the bishops’ conference said, “the consequences of changing marriage are very real,” and asked if organizations will be free to employ staff that is in line with their principles or if agencies will be excluded from bids for government contracts or other funding unless they endorse same-sex marriage.

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“We have seen each of these freedoms challenged overseas where the definition of marriage has changed,” the pamphlet said.

Last week, the Archbishop of Sydney, Anthony Fisher, expressed fears that people working for religious organizations could face anti-discrimination tribunals if they disagreed with same-sex marriage.

“What protections will be ­offered to people who work for church-run institutions such as schools, hospitals and universities?” Fisher asked. “Will teachers be free to teach church teaching on marriage or will they be forced to teach a more politically correct curriculum?”

According to a Newspoll comissioned by The Australian newspaper, 67 percent of Australians “definitely” plan on participating in the postal plebiscite, with another 15 percent saying they “probably” would vote.

The poll also showed 63 percent of the people plan on voting ‘Yes.’

However, the poll showed that the vast majority of Australians – 62 percent – also want any such legislation to include protections for religious freedom.