Photo: The Canadian Press. All rights reserved.

Nigel Wright, chief of staff for Prime Minister Stephen Harper, is shown appearing as a witness at the Standing Committee on Access to Information, Privacy and Ethics on Parliament Hill in Ottawa on Nov. 2, 2010. THE CANADIAN PRESS/Sean Kilpatrick

RCMP officials say Nigel Wright, former chief of staff to Prime Minister Stephen Harper, won't face criminal charges in connection with the ongoing Senate expenses scandal.

Wright resigned as Harper's right-hand man after it was disclosed he wrote a personal cheque for $90,000 to Mike Duffy to allow the disgraced former Conservative senator to repay disallowed housing expenses.

Investigators now say the evidence gathered "does not support criminal charges" against Wright.

"When the RCMP initiated the investigation, there were sufficient grounds to pursue the matter with regards to the offences of breach of trust, bribery, frauds on the government, as well as receiving prohibited compensation contrary to the Parliament of Canada Act," the Mounties said in a statement.

"Upon completion of the investigation, we have concluded that the evidence gathered does not support criminal charges against Mr. Wright."

In a statement distributed Tuesday by lawyer Peter Mantas, Wright sounded a note of vindication.

"My intention was to secure the repayment of taxpayer funds. I believed that my actions were always in the public interest and lawful," Wright said.

"The outcome of the RCMP's detailed and thorough investigation has now upheld my position."

In February, former Liberal senator Mac Harb and former Conservative senator Patrick Brazeau were charged with one count each of fraud and breach of trust — the first criminal charges to emanate from the scandal.

The Mounties continue to investigate allegedly fraudulent expenses claimed by Duffy and former Conservative senator Pamela Wallin.