Prime Minister Stephen Harper has appointed a former Reform MP to a committee that reviews the Canadian Security Intelligence Service.

The prime minister announced Monday that Deborah Grey is a member of the Security Intelligence Review Committee effective immediately.

The committee chair is Chuck Strahl, another former Reform MP who retired from politics in 2011. 

Established in 1984, the review committee also examines complaints by individuals or reports by ministers relating to security clearances and the national security of Canada.

The former head of the civilian board, Arthur Porter, resigned his position following media reports on his past business dealings.

He also faces allegations of fraud in one of the country's most expensive infrastructure projects.

Grey replaces another former Conservative MP and cabinet minister, Carol Skelton, who was appointed in 2010. Skelton served as the committee's acting chair following Porter's resignation and prior to Strahl's appointment. 

Skelton left the committee in May 2012.

There is a fifth potential vacancy on the committee, following Philippe Couillard's return to provincial politics in Quebec. He was elected as the leader of Quebec's Liberal Party in March. 

The prime minister's office says the government is not required to make appointments to fill all five spots.

NDP opposed appointment

Grey was an Alberta MP in Edmonton North for more than 15 years, first as a member of the Reform party, then the Canadian Alliance.

She was also first-ever female leader of the Official Opposition.

In 2007, she was appointed an officer of the Order of Canada for public service.

Grey is currently a speaker with the National Speakers Bureau.

The NDP told CBC News that leader Tom Mulcair was consulted on Grey's appointed and opposed it.

"I believe SIRC necessitates a nominee that is abreast of today's security intelligence environment and, preferably, steeped in Canadian and international law," a letter to the prime minister read. "Mrs. Grey's wealth of experience and training unfortunately fail to meet these requirements."

With files from CBC News