The court documents, released this afternoon, allege that Duffy filed eight separate expense claims that the RCMP says involved personal or partisan travel.
The claims were filed from June 2009 to September 2012.
The RCMP announced last week that it was charging Duffy with 31 criminal counts related to his expense claims, accusing him of misspending more than $200,000.
The charges stem from the disgraced senator's housing and travel expenses, and a $90,000 payment from Nigel Wright, the former chief of staff to Prime Minister Stephen Harper.
Duffy has denied any criminal wrongdoing. He could not be immediately reached for comment today on the new court documents.
The Conservative-appointed senator will appear in court on Sept. 16.