The political dramas that unfolded in courtrooms last year may be just the warm-up for a new year that will see former Conservative senator Mike Duffy on trial.

In 2014, Michael Sona was convicted of making illegal robocalls that sent voters in Guelph, Ont., to the wrong polling station for the May 2, 2011, federal election. And former Conservative MP Dean Del Mastro was found guilty of overspending on his 2008 campaign and faking paperwork to cover it up.

While those cases will continue in 2015, the coming year will also see a new batch of trials and investigations of politicians and political staffers.

Mike Duffy

The former Conservative senator and broadcaster will go to trial in April 2015 on charges of fraud, bribery and breach of trust. The court has blocked off eight weeks to deal with the case, which is bound to be covered extensively given Duffy's status as a household name and the bombshell allegations he's levelled against the Conservative Party. He'll also be the first to go to trial out of a group of four senators whose expenses have been questioned (one of the senators, Pamela Wallin, hasn't been charged in the expenses scandal).

None of the allegations have been tested in court.

Patrick Brazeau

The troubled senator, who was named to the Upper Chamber by Prime Minister Stephen Harper, will be in court starting June 1 for his preliminary inquiry. The court has set aside 12 days that month to deal with the proceeding that allows a judge to test the allegations and evidence before going to a full trial. Brazeau will be the second senator to go to trial among the group who are accused of claiming expenses to which they weren't entitled.

Brazeau also faces unrelated charges across the river from Ottawa in Gatineau, Que. He'll be in court there March 23-25.

None of the allegations have been tested in court.

Manon Perreault

Quebec MP Manon Perreault, who's now suspended from the NDP, appears on Parliament Hill in September 2011. ( Fred Chartrand/Canadian Press) Mascouche , Que., riding office. The Mounties sought copies of Perreault's expenses and any documents regarding her brother's hiring in her office, as well as copies of his expenses. The former New Democrat MP was kicked out of caucus after being charged with falsely accusing someone of theft and misleading police. Court records released earlier this month show she's also being investigated for fraud against the government and breach of trust. The RCMP obtained a production order for the House of Commons and a search warrant for her, Que., riding office. The Mounties sought copies ofexpenses and any documents regarding her brother's hiring in her office, as well as copies of his expenses.

Perreault has had court appearances regarding the charges of making a false allegation and misleading police.

No fraud or breach of trust charges have been filed.

None of the allegations have been tested in court.

​Mac Harb

The retired Liberal-appointed senator will be in court Aug. 10 to Sept. 4 to defend against charges of fraud and breach of trust. Harb paid back $231,000 in expenses and stepped down from the Senate about three months before his former colleagues voted to suspend Brazeau, Duffy and Wallin. Harb says he did nothing wrong and argued most senators filed the same type of expenses. Brazeau, Duffy and Harb are accused of claiming a housing allowance meant to allow senators who live outside the capital to cover their Ottawa-area living expenses.

The allegations have not been tested in court.

Bruce Carson

Carson was once a senior adviser to Prime Minister Stephen Harper and wrote a book about the Conservative movement, including his time in the PMO. After leaving government, Carson helped start a school of energy at the University of Calgary and worked with a water purification company. He now faces charges of influence peddling related to his work with both organizations.

Carson's trial on the charge related to the water purification company starts Sept. 8. A date for the charges related to the school of energy is likely to be decided in February.

None of the allegations have been tested in court.

Michael Sona

​Sona was sentenced to nine months in jail, but has been released on bail pending an appeal. While he's laying the groundwork to appeal the sentence, the Crown has already filed its motion to appeal the sentence too. There's no court date yet for the appeal hearing, but it's possible it could happen next fall.

Dean Del Mastro

The man elected three times as a Conservative MP resigned his seat hours before the House was to vote on whether to suspend him after he was found guilty of three charges related to his 2008 campaign. Del Mastro's sentencing hearing is scheduled for Jan. 27, although he said he would move to reopen the defence. He changed lawyers following that announcement and it's not clear whether he will follow through on that motion.

David Del Mastro

​Del Mastro's cousin also faces charges stemming from the 2008 federal campaign. The Crown alleges David Del Mastro, with the assistance of an employee, funnelled an additional $22,000 in donations to Dean Del Mastro's campaign. The case is working its way through the court with no trial date set.

The allegations have not been tested in court.

Investigation to watch: Pamela Wallin

Court documents show that RCMP were investigating suspended senator Pamela Wallin, but no charges have been laid. (Adrian Wyld/Canadian Press) It's been more than a year since court documents confirmed the RCMP were investigating former Conservative senator Pamela Wallin for fraud and breach of trust, and little more information has been available since then. Wallin hasn't been charged, and none of the allegations have been tested in court.

In a related high-profile case, the RCMP confirmed that its probe into Nigel Wright, Harper's former chief of staff, had ended without charges. It's likely the Mounties would do the same if they ended the investigation into Wallin.