After a dramatic week in Canadian politics that resulted in Prime Minister Stephan Harper losing two senators from his caucus and the resignation of his chief of staff, many wonder how the political shrapnel from this latest scandal will affect the Conservative government.

On Tuesday, Harper will hold an emergency caucus meeting ahead of a planned trip to Peru and Columbia for a trade mission. That meeting will be the first time since Nigel Wright's resignation on Sunday that Harper will face direct questions from members of Parliament, many of whom have said that the controversy is far from over.

Many Conservative senators and MPs have also said they are overwhelmed by the number of complaints they’ve been receiving from their constituents in recent weeks.

Harper will be joined by a new -- but familiar -- face, Ray Novak at Tuesday’s meeting.

Novak, 35, was named the new chief of staff following Wright's abrupt resignation.

The former Bay Street executive gave notice just days after CTV Ottawa bureau chief Robert Fife broke the story that the PMO's chief of staff wrote a personal cheque for $90,172 to help Sen. Mike Duffy cover the repayment of improper housing expenses.

Wright's resignation followed that of Duffy's, who left the Conservative caucus Thursday. He will be sitting as an independent.

Duffy's colleague, Sen. Pamela Wallin was forced out of caucus on Friday. She is facing her own audit looking into her travel expenses.

Critics call for answers

The three departures, however, will likely do nothing to quash the Senate controversy.

Following news of Wright's resignation, NDP ethics critic Charlie Angus said the Harper government is in "full-fledged panic mode."

Some are also saying the controversy will continue to rage on as questions mount about Harper and the PMO.

"This is about Mr. Harper. This is about the Prime Minister’s Office, how the Prime Minister’s Office operates and the ethical and legal standards by which it operates," Liberal foreign affairs critic Bob Rae said on Sunday. "That’s where the focus is, and that where it belongs."

Rae added that an independent investigation into the matter is needed.

"If the Conservatives are not prepared to let it go to a parliamentary committee, then they need to appoint a special investigator or someone who has the capacity to ask all the difficult questions."

Rae's call for an investigation comes after the New Democrats last week asked Senate Ethics Officer Lyse Richard to look into the matter, saying the $90,000 cheque from Wright broke ethics rules that ban senators from accepting gifts.

According to the Senate Conflict of Interest Code, gifts over $500 must be reported within 30 days.