SINGAPORE (AP) – Authorities in Singapore on Friday banned a gay rights forum at which a retired Canadian law professor was to speak, the second time in a week the city-state has forbidden an event that touches on gay issues.

The forum was to feature Douglas Sanders, a professor emeritus in law at the University of British Columbia, Canada, and Thailand’s Chulalongkorn University, the event’s organizer, Alex Au, told The Associated Press.

But because the Aug. 7 forum, titled “Sexual Orientation in International Law: The Case of Asia,” was deemed contrary to public interest, police canceled the event’s license Friday and immigration authorities rejected Sander’s visa application, Singapore’s Home Affairs Ministry said.

“Our laws are an expression and reflection of the values of our society; the discourse over a domestic issue such as the laws that govern homosexuality in Singapore must be reserved for Singaporeans … foreigners should refrain from interfering,” the statement said.

But Mr. Au, the forum’s organizer, said Sanders had no such intention.

“He was going to do a lecture in Singapore about international trends. He is not an expert on Singapore and had no intention of talking about Singapore,” Mr. Au said.

Singapore’s censors earlier in the week banned an exhibition of photographs depicting gay men and women kissing, also organized by Au, saying the images “promote a homosexual lifestyle, and cannot be allowed.”

The prohibitions have come amid a debate in the city-state on whether gay sex should be decriminalized. Singapore’s founding leader, Lee Kuan Yew, a few months ago questioned the ban on gay sex, saying the government should not act as moral police.

Under Singapore law, gay sex is punishable by a maximum of two years in jail. Authorities have banned gay festivals and censored gay films, but despite the official ban on gay sex, there have been few prosecutions.