OTTAWA -- Premature leaks of auditor general Michael Ferguson's damning report on senators' expenses has some senators seeing red.

They agreed Tuesday to order the Senate rules committee to investigate and attempt to determine the source of the leaks.

The reference to the rules committee followed a complaint by Liberal Sen. Celine Hervieux-Payette, who said the leaks undermined the fundamental right of senators named in Ferguson's report to the presumption of innocence and a fair and equitable defence.

Moreover, she said they've caused unheard-of damage to the institution and hampered the Senate's operations.

"Few people had access to the report last Thursday," she noted.

The contents of Ferguson's scathing report began leaking almost immediately after he formally delivered it to Senate Speaker Leo Housakos last Thursday.

It was supposed to remain confidential until it was tabled in the Senate on Tuesday.

"I was one of the first victims of these leaks ... which cause me a great deal of embarrassment," government Senate leader Claude Carignan said, supporting Hervieux-Payette's call for an investigation.

One of the first leaks was news that Carignan, Housakos and Liberal Senate leader James Cowan -- the same trio who created an independent arbitration process for senators who want to appeal Ferguson's findings -- were among the 21 sitting and former senators flagged in the audit for making ineligible expense claims.

Another nine were so egregious that Ferguson recommended their cases be referred to the RCMP.

Hervieux-Payette, who was not among those red-flagged, said some of the named senators felt "trapped" by oaths of confidentiality to say nothing until the audit report was finally tabled. For six days, their reputations were damaged while selected details about their expenses appeared in the media, she said.

The report itself gives each named senator a chance to defend himself or herself and to explain the disputed expense claims.