The Senate is moving to suspend senators Mike Duffy and Pamela Wallin from the red chamber without pay, CBC has learned.

At the same time, Duffy has sent a letter to the Speaker of the Senate, Noel Kinsella, requesting a medical leave of absence because of a heart condition.

Three motions were read in the Senate shortly after 2:40 p.m. ET that would strip Wallin and Duffy of not only their pay, but also Senate resources and benefits. One of the motions would also reinstate a suspension of Senator Patrick Brazeau, but also dock his pay and benefits, as well as the use of his office.

Duffy and Wallin have both repaid money to the Senate after questions about their expense claims. Duffy repaid more than $90,000 in March with a personal cheque from Prime Minister Stephen Harper's former chief of staff. Wallin complied with a Senate order to repay more than $140,000, including interest, in September.

Both senators were subjects of damning forensic reports from the accounting firm Deloitte about inappropriate spending. Duffy is now being investigated by the RCMP over his Senate expense claims.

A Conservative notice of motion to suspend Wallin and Duffy came from government Senate leader Claude Carignan in the Senate's first meeting since the House was prorogued last June.

In the motion related to Wallin, Carignan stated, "The Senate orders a suspension for the Honourable Senator Wallin for sufficient cause, considering her gross negligence in the management of her parliamentary resources until such time as this order is rescinded."

The motion, under Senate rules, can't be debated for at least 48 hours. A debate will take place at the Senate's next session on Tuesday.

After a debate, the motion will be put to a vote that requires a simple majority to pass. The Conservatives have a majority in the Senate.

Senators can make their case

Carignan, speaking to reporters in the Senate foyer, said the three senators will have a chance to defend themselves when the motion is debated. Duffy, he said, "will have the opportunity to move amendments. He can make his case Tuesday."

Asked if the behaviour of the three senators reflected badly on the judgment of Prime Minister Stephen Harper, since they were his appointees, Carignan said, "This isn't [about] a Liberal, a Conservative or an Independent. This is about a senator who didn't respect the dignity and rules of the Senate."

The suspensions, Carignan said, would last until the end of the session, a period of two years until the next general election will be called.

The Liberal leader of the Senate, James Cowan, told reporters he was surprised the Senate's Conservative-dominated internal economy committee didn't sanction the senators as soon as it found they had inappropriately claimed expense money. "I don't think it's enough to simply pay the money back," he said.

He said his Senate caucus members will discuss how they will vote on the motion when they meet on Tuesday morning. Although he said he hasn't yet formed a final opinion, Cowan said, "these were not simple mistakes… there was a pattern of abuse," regarding how Duffy, Wallin and Brazeau filled out their expense forms.

Cowan defended the right of the Senate to impose disciplinary sanctions, although none of the three senators has been charged with any offences relating to expenses.

Opposition NDP Leader Tom Mulcair told reporters after question period, "What do you call three senators suspended without pay? A good start. We'd suspend all of them without pay." The NDP's position, a central pillar in its strategy this session, is to abolish the Senate.

Several Liberal senators expressed reservations about what they said was the lack of due process and fairness in the treatment of the three senators. "They [the Conservatives] are doing it for the polls," said Liberal Senator George Baker.

Conservative Senator Hugh Segal, an old friend of Wallin's, issued a statement saying he could not support the motion. "The motion in Senator Wallin's case seems both ill-informed, inconsistent with the many problems in the report of the board of internal economy which itself has never been discussed in any way in the Senate."

Brazeau's suspension would be toughened

Brazeau, who is also under investigation by the RCMP for his expense accounts, was suspended earlier this year by the Senate after he was charged for sexual assault in a separate matter. Days after his charge, the Senate voted unanimously to suspend him with pay, in a motion that stated in order to "protect the dignity and reputation of the Senate and public trust and confidence in Parliament, the Senate order a leave of absence."

The motion on Thursday that would reinstate his suspension is a tougher one, removing his pay, benefits and use of any Senate resources including travel funds and telecommunications.

It's not known if Brazeau has asked the Senate for a medical leave. However, some of the court dates in his sexual assault charge have been moved because of the state of his health. A few weeks ago, after police were called to a house in Gatineau, Que., Brazeau was taken to a local hospital.

Senate sources say Duffy's request for a medical leave will not override a move to suspend him, because a suspension would be a "disciplinary sanction for an unrelated matter."

In the letter about his state of health, Duffy wrote, "When I had open heart surgery in 2006, they found three blockages. Because of bleeding, broken ribs and various complications, they ended up fixing the main problem, but did not want to keep me on the table longer to fix the other two blocked vessels. They suggested that surgery could come later."

Over the summer, Duffy said, he suffered unstable angina and ended up in hospital in Halifax for two days. He said his doctor recommended he stay off work "until I get the all-clear from my medical team."