TORONTO -- A Canadian Muslim organization is calling on Ottawa to spell out how it decides whether to allow controversial foreign speakers into the country ahead of a planned appearance by two conservative American bloggers.

The National Council of Canadian Muslims worries Pamela Geller and Robert Spencer will spread "hate and misinformation" about the Islamic faith when they speak at a Toronto-area hotel Tuesday evening, the group's executive director said.

Though it disagrees with their message, the group isn't seeking to have the pair turned away at the border, Ihsaan Gardee said. But it would like to know how, exactly, that decision is made.

"What we would like from the government of Canada is clear and consistent direction... when it comes to the eligibility of speakers to enter Canada," he said.

"It needs to be consistent and clear because if it isn't, then it sends a message that freedom of speech and hate (are) being arbitrarily measured."

Canadian authorities have previously denied access to some polarizing figures, such as Terry Jones, the American pastor best known for burning copies of the Islamic holy text.

Geller and Spencer have sparked their share of outrage through their respective blogs, Atlas Shrugs and Jihad Watch. The pair also co-founded the group Stop the Islamization of America.

They were barred from entering the U.K. in June, a move they condemned as a blow against freedom of speech.

The Canada Border Services Agency wouldn't say whether it would consider similar action, noting admissibility is determined "on a case-by-case basis."

"Several factors are used in determining admissibility into Canada, including: involvement in criminal activity, in human rights violations, in organized crime, security, health or financial reasons," spokeswoman Vanessa Barrasa said in an email.

But recent changes to the Immigration and Refugee Protection Act also allow the immigration minister to deny entry over "public policy considerations," a standard some experts say has been ill-defined.

Under the previous rules, "it was very clear that the offence in question had to be equivalent to a criminal offence in Canada," said Sharryn Aiken, a law professor at Queen's University in Kingston.

"The whole problem with the public policy grounds is it vests an enormous amount of discretion in the minister to define what are these exceptional circumstances that warrant the exercise of this power," she said.

A government backgrounder issued earlier this year said the minister could use his authority to bar anyone "who has a history of promoting violence against a particular religious group."

The document also said new regulations must be put in place before the minister can use this new power, but Citizenship and Immigration Canada refused to say whether that had occurred.

Aiken argues there are more effective ways to protect Canadians against hateful rhetoric while still defending free speech.

"I would much rather see the government put its money where its mouth is and enforce our hate-crime laws in this country than pre-emptively bar people at the border," she said.

The National Council of Canadian Muslims, meanwhile, said it still hopes the event will be called off.

The organization unsuccessfully petitioned the Hilton hotel to cancel the talk titled "The Dangers of Islamic Extremism and Western Complacency," which is sponsored by the Toronto-based Jewish Defence League of Canada.

The Jewish group's national director, Meir Weinstein, said any attempts to shut down the event amount to censorship -- a view embraced by the bloggers themselves.

"(The NCCM) is desperate to shut down any and all honest discussion of jihad violence and Islamic supremacism, and to stigmatize all who engage in such discussion with smear charges of 'racism' and 'bigotry,' so as to intimidate people into thinking there is something wrong with resisting jihad terror," Spencer said in an email.

Geller said the controversy is "part of larger effort to silence, demonize and marginalize everyone who tells the truth about Islam and jihad."

"They can't refute me. So they resort to these thuggish tactics to try to silence me," she said in an email.

It's the second time the Jewish Defence League has hosted Geller. Last year's event was sold out, the group said.