Cran Campbell, 64, has been flagging postings under a heading called rants and raves in the personals section of the company's Vancouver site and calling on police, human-rights tribunals and politicians across Canada to take action.
He wants authorities to force companies that maintain Internet servers outside the country but use the .ca domain name at the end of their URL addresses to comply with Canada's hate-speech laws.
Campbell has faced several obstacles in his efforts to draw attention to what he says is wrong.
Individuals behind websites with .ca domains don't need to live in Canada or operate their Internet servers here, and the organization that manages those domain names doesn't mandate what laws people must follow.
And police say Canada's hate-speech laws are complex.
"I can't stop doing it because it's just not right," Campbell said, adding he has been threatened because of his actions. "That's how these people, when they do this, this is how they get their foothold in it because other people get worried about doing anything about it.
"The fact is that's how they get bigger, so, you know, they've just knocked on the wrong door with me."
Campbell said the number of offensive comments on Craigslist has increased in the last year.
Motivated by his hatred of the racism he saw as a child in Prince George, B.C., and in the U.S. military as a young adult, Campbell said he now spends a couple hours a day flagging comments on Craigslist, a classified ads site for items and services.
Campbell said he has reported his concerns to Craigslist officials in an email but has not received a response.
Recent comments archived from the site by The Canadian Press have included "rants" about the "destruction of the white race," jokes about Asian immigrants and calls for First Nations and Canadians of European descent to unite.
One post threatened violence against a current Member of Parliament, while another poked fun at Caucasians for being "too lazy to work hard."
Another person even threatened to "come and take care" of whoever has been flagging comments for removal.
Campbell said that in one post someone said the flagger should be squashed like a bug and in another a person threatened to send people after whoever wants the comments removed.
Campbell said the threats appeared to be directed specifically at him.
The identity of those posting the comments is unknown because individuals can post anonymously.
Const. Ciaran Feenan of the Delta Police Department said authorities have not received a complaint from Campbell about threats in about a year, and while the last complaint was investigated, it didn't meet the threshold for taking further action.
But Feenan said the investigation is ongoing, and police have told Campbell to report any additional threats.
He said such investigations can be difficult because officers have to try to find someone at the other end of a computer, which could be outside the country.
The Canadian Human Rights Commission said it can't comment on any specific complaints because it wants to ensure "the confidentiality of the dispute resolution process and to protect the rights of both respondent and complainant."
Michael Stewart, a spokesman for the Canadian Internet Registration Authority, said his member-driven organization, which manages domain names ending with .ca, doesn't specify where an individual should live or where their servers must be located.
He said it does require them to meet "Canadian presence requirement."
The requirements are set out in a four-page document that allows a registrant to be a Canadian citizen, a permanent resident, legal representative or corporation to a library, archive or museum or educational institution.
The authority also doesn't mandate what laws a person must follow, Stewart said.
"However, every registrant agreement is governed by Canadian law and each registrant agrees to submit to the jurisdiction of Canadian courts for issues arising from that agreement," he said in an email to The Canadian Press.
Stewart said his organization refers individuals who have concerns about a website's content to "those best equipped to handle those concerns, such as police, the courts, regulators, etc."
An email to the Department of Justice about whether any investigation has been launched in connection with Campbell's concerns was referred to the RCMP.
Investigating such complaints and enforcing the country's hate-speech laws isn't easy, said Det. Const. Terry Wilson of the B.C. Hate Crime Team, a two-person integrated unit that includes a member from the RCMP and New Westminster Police Department.
Wilson said authorities investigating complaints about hate speech must meet several tests under the hate propaganda section of Canada's Criminal Code.
He said a message has to be made publicly and must target one of five identifiable groups based on race, colour, religion, ethnic origin, or sexual orientation.
Police must also determine whether a person is tying to cause disdain or hatred towards that group, Wilson said.
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