A chronology of the Senate expenses scandal

Another chapter in the Senate expense scandal closed Wednesday with the Crown officially withdrawing charges of fraud and breach of trust against SenatorPatrick Brazeau. Here is a timeline of the scandal.

June 13, 2012: Auditor general Michael Ferguson releases a study of Senate expense claims; in some cases Senate administration didn't have the right documents to support claims for travel and living expenses. No senators are named in the review, which only looked at a small number of claims.

Nov. 21, 2012: A Senate committee is asked to examine housing allowance for Brazeau, a Conservative senator who lists a home in Maniwaki, Que., as his primary residence despite appearing to live full-time within a 100-kilometre radius of Ottawa.

Dec. 3, 2012: Similar questions are raised about Conservative Sen. Mike Duffy, who claims a primary residence in P.E.I. despite being a longtime Ottawa resident.

Dec. 6, 2012: The Senate expands its audit of housing expenses to include Liberal Sen. Mac Harb, who claims a home near Pembroke, Ont., as his primary residence despite being a longtime Ottawa politician. The upper chamber begins examining residence claims of all senators, who are constitutionally bound to be residents of the provinces they represent.

Feb. 8, 2013: Senate hires external auditing firm Deloitte to review Brazeau, Duffy and Harb expense claims.

Feb. 28, 2013: Senate audit fails to turn up any questionable housing allowance claims beyond those of Brazeau, Harb and Duffy.

May 9, 2013: Senate releases a report into housing claims, along with the Deloitte audits. Deloitte says the three senators live in Ottawa area, but that the rules and guidelines are unclear, making it difficult to say categorically that anyone broke the rules. Harb and Brazeau are ordered to repay $51,000 and $48,000, respectively. Harb says he will fight the decision.

May 12, 2013: RCMP says it will examine Senate expense claims.

May 14, 2013: Brazeau says he also broke no rules and is exploring all options to overturn an order to pay the money back.

May 16, 2013: Duffy resigns from Conservative caucus amid revelations that the Prime Minister's Office worked behind the scenes to quash Duffy's audit and that chief of staff Nigel Wright gave Duffy a personal payment to help repay about $90,000 in expense claims.

May 17, 2013: Sen. Pamela Wallin announces she's leaving the Conservative caucus. Her travel expenses, which totalled more than $321,000 since September 2010, have been the subject of an external audit since December.

June 3, 2013: Sen. Marjory LeBreton, the Conservative leader in the Senate, says she intends to ask the auditor general to look into all the expenses of the upper chamber. LeBreton says she will introduce a motion calling for a comprehensive audit of expenses.

June 13, 2013: Brazeau and Harb are given 30 days to reimburse taxpayers for their disallowed living expenses bills that together total more than $280,000.

Aug. 13, 2013: The full extent of Wallin's questionable expenses are laid bare as the Senate releases an audit of her travel claims, calls in the Mounties and orders her to repay tens of thousands of dollars.

Aug. 21, 2013: Wallin is informed she would have to reimburse the Senate a grand total of $138,970 for ineligible travel expense claims. Wallin was already on the hook for $121,348 after an independent audit of her travel expenses.

Aug. 26, 2013: Harb resigns from the upper chamber after having earlier left the Liberal party to sit as an independent. He also drops a lawsuit and promises to repay his questioned living and expense claims.

Sept. 6, 2013: Wallin is told she has until Sept. 16 to repay tens of thousands of dollars in ineligible travel expenses.

Sept. 13, 2013: Wallin pays back her dubious travel claims while accusing some fellow senators of succumbing to a "lynch mob" mentality. The Saskatchewan senator says she has paid back $100,600, plus interest, on top of $38,000 already repaid all from her own funds.

Oct. 17, 2013: Claude Carignan, the government's new leader in the Senate, introduces motions to suspend Duffy, Wallin and Brazeau from the Senate. The motions call for the three to be stripped of their pay, benefits and Senate resources.

Oct. 22, 2013: In an explosive speech in the Senate chamber, Duffy accuses Prime Minister Stephen Harper's office of orchestrating a "monstrous fraud" aimed at snuffing out controversy over his expenses. Duffy accuses the prime minister of being more interested in appeasing his Conservative base than the truth.

Oct. 23, 2013: Wallin follows Duffy's lead with her own speech in the Senate, describing the suspension motion against her as "baseless and premature" and designed "to remove a perceived liability, namely me."

Oct. 25, 2013: Brazeau drops a bombshell of his own, saying Carignan earlier that same day took him aside and offered him "a backroom deal": apologize publicly for his actions in exchange for a lighter punishment. Carignan acknowledges the conversation but described the offer as one made out of "friendship."

Oct. 30, 2013: Senate Speaker Noel Kinsella rules that an attempt to cut off debate on motions to suspend Duffy, Wallin and Brazeau from the Senate is out of order. This delays again the effort to suspend the trio.

Nov. 1, 2013: Documents filed in court by the RCMP explicitly allege Wallin "did commit breach of trust in connection with the duties of office" and "by deceit, falsehood or other fraudulent means defrauded the Senate of Canada of money by filing inappropriate expense claims," contrary to the Criminal Code. The documents include a request for several versions of Wallin's electronic Senate calendar, citing them as further evidence that could back up the allegations.

Nov. 4, 2013: Brazeau addresses the Senate chamber, making an emotional appeal for senators to reconsider his case. At one point, he addresses his children: "It is very important that you understand that I am not guilty of what some of these people are accusing me of.... I am not a thief, a scammer, a drunken Indian, a drug addict, a failed experiment or a human tragedy."

Nov. 5, 2013: Senators vote to suspend Brazeau, Duffy and Wallin without pay but with health, dental and life insurance benefits intact for the remainder of the parliamentary session, which expired with the election call in 2015.

Jan. 29, 2014: Liberal leader Justin Trudeau expels the 32 Liberal senators from his caucus in what he calls an effort to reduce partisanship in the upper chamber. He says if he becomes prime minister he would appoint only independent senators, chosen through an open, public process.

Feb. 4, 2014: The RCMP lay charges of fraud and breach of trust against Harb and Brazeau.

July 17, 2014: The RCMP charge Duffy with 31 counts of fraud, breach of trust and bribery.

May 26, 2015: The Senate appoints Ian Binnie, a retired Supreme Court of Canada justice, as a special arbitrator for questioned expenses being found in the review by auditor general Michael Ferguson.

June 9, 2015: Auditor general Michael Ferguson releases an audit that flags 30 senators for questionable expenses, including nine that he recommends be sent to the RCMP for review.

March 21, 2016: Binnie releases his report. He says in 10 of 14 cases of questioned expenses, he reduced the total. Senators were often mixing personal business with Senate business in order to better justify their travel claims. He says he imputed no bad motives to any of the senators, who generally didn't understand the rules governing their spending.

April 21, 2016: Duffy is acquitted on all counts and returned to the Senate in full standing.

May 19, 2016: The RCMP say they will not lay charges against Wallin, ending a three-year investigation.

May 20, 2016: Prosecutors drop charges against Harb, saying they saw no reasonable prospect of conviction.

July 13, 2016: Prosecutors drop the charges against Brazeau, saying they saw no reasonable prospect of conviction. Brazeau is returned to the Senate in full standing.