Mike Duffy trial: Senate invokes immunity to block defence bid for documents

The Senate is using the closed-door hearings involving a disgraced former Liberal senator as a precedent for keeping internal audit information out of the Mike Duffy trial.

Then-senator Raymond Lavigne was convicted in 2011 of fraud and breach of trust for using Senate funds for work on his property and for travel by staff members.

• Senate moves to keep internal report on residency secret

In 2006, a special Senate committee reviewed his expenses in private and decided to refer the matter to the RCMP.

But the transcripts of those hearings were kept out of Lavigne's trial, as the Crown asserted parliamentary privilege or immunity.

Now, the Senate's lawyers argue in a court affidavit that the details of a 2013 internal audit on the residency status of all senators should also be kept from the courts.

Duffy faces 31 charges of fraud, breach of trust and bribery in connection with his Senate travel, living and office expenses.