Harper also announced that the government has asked the Commission for Public Complaints Against the RCMP to look into the allegations raised in the report released Wednesday by the respected New York-based rights watchdog.
"If Human Rights Watch, the Liberal party or anyone else is aware of serious allegations involving criminal activity, they should give that information to the appropriate police so that they can investigate it," Harper told the House of Commons in response to a question by interim Liberal leader Bob Rae.
"Just get on and do it."
The report accuses RCMP officers of abusing aboriginal women and girls in northern B.C., including one allegation of rape.
The alleged incidents were uncovered as part of a broader investigation into charges of systemic neglect of missing and murdered aboriginal women along B.C.'s Highway 16, nicknamed the "Highway of Tears."
The Liberals and NDP joined the Assembly of First Nations is pushing the government to adopt the core recommendation of the report — that the federal and B.C. governments participate in a national commission of inquiry into the matter.
"We must make all efforts to ensure our citizens are protected, and that includes action by all parties — governments, police, citizens and families," said AFN National Chief Shawn Atleo.
"The stories shared in this report are heart-wrenching and absolutely appalling, particularly given this is only a small sample of the conditions and experiences of indigenous women, girls and families across our territories."
The RCMP wants to get to the bottom of abuse allegations against its officers, but Human Rights Watch isn't helping police to investigate, RCMP Chief Supt. Janice Armstrong said in a statement.
None of the complainants have come forward since the organization approached the Mounties about the allegations five months ago, so police haven't been able to investigate further, she said.
"These allegations must be brought forward for proper investigation," Armstrong said, noting that the force takes the allegations very seriously.
"Unfortunately, five months later and none of these allegations have been brought forward for investigation. It is impossible to deal with such public and serious complaints when we have no method to determine who the victims or the accused are."
Rae called for the criminal allegations to be referred to an outside police force because the RCMP should not be expected to investigate allegations of criminal conduct by its own members.
"If an allegation is made against the Ottawa police force, it's not the Ottawa police force that investigates that allegation. It's investigated by another police force," said Rae.
"The problem is that clearly there's been a breakdown of confidence with respect to people coming forward in those situations that have been described by Human Rights Watch."
Human Rights Watch undertook the investigation last year after a Vancouver-based agency approached it in 2011 complaining that authorities in Canada were not doing enough to address the problem.
"After years of hearing stories and doing our best to try and get some accountability, we felt we owed it to the girls to take the next steps, to try and get some kind of investigation and bring these allegations and abuses to light," said Annabel Webb, the founder of the Vancouver group Justice for Girls, which works with poor, troubled teens.
Meghan Rhoad, the report's lead researcher, said she wants the police to be held accountable.
"Policing is failing in terms of protection of indigenous women and girls in northern B.C., certainly based on our research."
Researchers spent five weeks in 10 northern B.C. towns last summer and conducted 87 interviews with 42 indigenous women and eight indigenous girls from age 15 to 60.
The most serious allegation involved a woman who told researchers that she was raped and threatened with death by four RCMP officers after she was abused in a remote location.
Other allegations include: young girls being pepper sprayed and shocked with a Taser; a 12-year-old girl being attacked by a police dog; a 17-year-old girl being repeatedly punched by an officer; women strip-searched by male officers; and women injured by excessive force during their arrests.
"In five of the 10 towns Human Rights Watch visited in the north, we heard allegations of rape or sexual assault by police officers," the report states.
"Human Rights Watch was struck by the level of fear on the part of women we met to talk about sexual abuse inflicted by police officers."
Rhoad said about a dozen young women cancelled interviews with researchers because they were too scared of repercussions from police officers working in their small communities.
Samer Muscati, a Canadian co-researcher, said the level of fear among the women interviewed was on par with what he's encountered while researching abuses by security forces throughout the Middle East, Iraq, Libya and Sudan.
"You expect that level of fear when you're in a place like Iraq, in a post-conflict country where security forces are implicated in horrible abuses," said Muscati.
"But in Canada, where police are known to protect citizens, it is quite alarming to hear the stories of women and girls, particularly."
The report contains a number of testimonials from women whose identities have all been protected.
The most serious is from a homeless woman identified as Gabriella P., who described being raped by four Mounties. She told researchers she knew the names of the officers, but refused to provide them.
"I feel so dirty," a tearful Gabriella is quoted as saying in the report. "They threatened that if I told anybody they would take me out to the mountains and kill me and make it look like an accident."
Webb said it has been difficult to bring the allegations to light because the girls themselves don't believe in the justice system.
Webb said she hopes that upstanding members of the RCMP are outraged enough by the report to drive out their more abusive colleagues.
"First and foremost, I'd like to see a stop to the abuse," she said. "If we could just stop the abuse, that would be kind of a banner day."
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