Credits: FILE PHOTO
Carson, who has previous criminal convictions, served as Harper's chief policy analyst and fixer from 2006 to 2008 before leaving to lead the Canada School of Energy and the Environment in Calgary. He later returned to the Prime Minister's Office briefly in 2009.
He is alleged to have accepted commission from a third party in connection to a government business matter. The RCMP said it has been investigating Carson since March 2011 after it received a referral from the PMO.
He is set to appear before an Ottawa court in September.
The PMO's referral to the RCMP was prompted after an investigative news report aired on the Aboriginal Peoples Television Network (APTN) in March 2011.
APTN's story probed Carson's relationship with Ottawa-based water company H2O Pros and said documents revealed how the former Harper aide promoted the business to bureaucrats in the aboriginal affairs department.
The report also said Carson was engaged to a former escort who had a financial connection to the company.
Harper's spokesman Andrew MacDougall said the government immediately referred the matter to the RCMP commissioner, the ethics commissioner and the lobby commissioner after it was informed of the allegations.
"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 a statement.
NDP ethics critic Charlie Angus said there are still serious questions about how Carson was able to obtain work in the PMO with existing convictions on his record. Carson was convicted of five counts of fraud dating back to the '80s and '90s.
"How is a convicted felon brought into the inner sanctum of the Prime Minister's Office? Did they not know or did they not care?" Angus said. "At the end of the day, it is the prime minister that has to take responsibility for the fact that he decided a convicted felon was the kind of guy that he wanted to get advice from."