A Canadian tech company is under growing scrutiny for helping some of the world’s more repressive regimes filter online content, prompting calls for Ottawa to establish a clear foreign policy for cyberspace.

Netsweeper Inc., based in Guelph, Ont., has provided services for telecommunications companies in Qatar, United Arab Emirates, and Yemen, according to the Open Net Initiative.

In those countries it has blocked websites related to homosexuality, sex education and human-rights advocacy, as well as some newspapers and blogs and proxy websites that allow Internet users to browse anonymously, according to testing conducted by Open Net.

It’s apparently not alone.

The head of University of Toronto’s Citizen Lab, which is a partner in Open Net, said Netsweeper is one of several North American companies used by repressive regimes abroad. U.S. companies such as Websense and McAfee SmartFilter have also been used by governments in the Middle East and North Africa, according to Open Net.

“It’s a bit of an ugly market for them, one that is very lucrative but obviously doesn’t sell well in terms of public profile,” Professor Ronald Deibert told The Canadian Press.

Open Net is a joint partnership between the Citizen Lab, the SecDev Group in Ottawa, and the Berkman Center for Internet and Society at Harvard University.

Netsweeper did not respond to an interview request and in the past has said it won’t comment on the issue.

The company has, however, outlined on its website some of the services it offers governments, in addition to those available for schools and businesses.

“A recent trend gaining more traction each day is government bodies taking more responsibility and controlling what information is available and being viewed on the Internet within their region or country,” says a statement on the site.

It says Netsweeper enables governments “to enforce safe and positive Internet environments.”

But the company has come under criticism for its services, which watchdogs argue stifle basic freedoms online.

Jacob Appelbaum, a prominent U.S. computer researcher and hacker, singled out Netsweeper during a visit to Montreal earlier this month.

Through his own testing, he found that Netsweeper is helping filter content in Qatar.

Appelbaum is one the coordinators of the Tor Project, an initiative aimed at determining what kinds of monitoring and restrictions are in place in countries around the world.

“Some of this stuff is pretty sketchy,” Appelbaum said during a hacker conference in Montreal earlier this month.

“They are selling devices that are used to de facto harm people,” by limiting people’s access to information, he said.

But Qatar is far from the worst, according to Appelbaum.

In his presentation, he offered details of internet surveillance and censorship in places like Iran, Lebanon, China, Bahrain, and Syria.

Syria, he said, is particularly scary.

He said he was hesitant even discussing that country’s practices, out of fear for his own personal safety: “When you go to certain websites, you get a visit from the secret police.”

Deibert, who is preparing a more detailed report on Netsweeper’s content filtering with Open Net, said the company’s activities are further proof the federal government needs to develop a clear foreign policy for cyberspace.

He suggests one possible formula: take a major international treaty of the 20th century, and apply it in a decidedly 21st century context.

Canada could take a hardline stance, he said, by introducing legislation making it illegal for Canadian companies to filter content in countries that violate the freedoms outlined in the United Nations Declaration of Human Rights.

But that could be a tall order, given the revenue at stake for Canadian companies in foreign markets.

Research In Motion Ltd., for instance, has faced pressure to comply with the demands of foreign governments.

Earlier this year, the Waterloo, Ont.-based company agreed to block access to pornography in Indonesia after the country threatened to revoke its operating license.

RIM faced threats of service bans last year from Saudi Arabia and the United Arab Emirates over demands to have access to communications on BlackBerry devices.

But Deibert said Canada should take a clear position on content filtering and, at the very least, avoid providing assistance to companies like Netsweeper.

In the past, Netsweeper has received funding from the National Research Council.

Deibert said Canada could assume a leadership role on cyberpolicy, where “we would be actively working in international forums to spotlight and develop a kind of normative agreement that is consistent with the values we hold as a country.”