The RCMP has charged Bruce Carson, a former adviser to Prime Minister Stephen Harper, with influence peddling, also known as “fraud on the government.”

Carson, 66, is alleged to have accepted a commission for a third party in connection with a business matter relating to the government. Police offered few details Friday of the allegations against him.

The RCMP began investigating Carson in March 2011, after receiving a referral from the Prime Minister’s Office. That followed a report from Aboriginal People's Television Network that questioned how Carson used his government connections to help his 22-year-old girlfriend.

According to the APTN investigation, Carson's girlfriend and former escort, Michele McPherson, acted as a liaison between H20 Pros and the First Nations communities, and stood to earn commissions from any sales of water systems.

Andrew MacDougall , the PMO’s director of communications, says after being informed of the allegations last year, the government referred the matter to the RCMP Commissioner, the Ethics Commissioner and the Lobbying Commissioner.

“Any individual who doesn't respect our laws must face their full force as well as the consequences that come with them,” MacDougall said in an email to CTV News.

Carson’s lawyer, Pat McCann, said his client intends to “vigorously defend the allegation.”

Carson had been convicted of five counts of fraud before he became one of Harper’s closest advisers.

He was disbarred by the Law Society of Upper Canada in the 1980s for two counts of defrauding clients.

In 1990, he pleaded guilty to defrauding a car rental company and two banks of sums exceeding $1,000 each.

Carson’s lawyer has previously said that his client disclosed his entire criminal record during a security check before joining the PMO.

Opposition parties wasted no time blasting the Conservatives after the latest charges against Carson were announced.

"The Prime Minister still hasn’t explained, or taken any responsibility, for how his inner circle included someone with previous criminal convictions for fraud -- who then went on to allegedly use his political connections to take advantage of impoverished First Nations communities for a quick buck,” NDP ethics critic Charlie Angus said in a statement.

“As usual, Conservatives only acknowledge their ethical problems after they are caught."

In a statement, Liberal privacy and ethics critic Scott Andrews said Harper “seems to have a penchant for surrounding himself with shady characters.”

Carson’s first court appearance is scheduled for Sept. 10, in Ottawa.

With files from The Canadian Press