TORONTO -- The Ontario Provincial Police are investigating allegations of bribery and corruption after a former Liberal candidate said he was offered a job or appointment to step aside for Premier Kathleen Wynne's choice in a Sudbury byelection. Wynne has denied the allegations.

Here are some key dates in the scandal:

Nov. 20: Sudbury New Democrat MPP Joe Cimino resigns after just five months on the job, citing "personal health wellness."

Nov. 26: Sudbury Liberal riding association agrees to hold nomination meeting to select byelection candidate.

Nov. 30: Premier Kathleen Wynne meets with NDP MP Glenn Thibeault, who agrees to run for the provincial Liberals. Wynne has said she decided at that meeting to appoint him.

Dec. 11: Local Liberal and chair of the Sudbury police services board Gerry Lougheed visits Andrew Olivier, the failed Liberal candidate in the June provincial election who was seeking to run again. Lougheed asks Olivier to consider stepping aside and nominating Thibeault and tells Olivier "in the course of that deliberation" to consider "appointments, jobs, whatever."

Dec. 11: Wynne phones Olivier, who is quadriplegic and tapes conversations as his way of taking notes. He says technical difficulties prevent him from recording that exchange.

Dec. 12: Pat Sorbara, Wynne's deputy chief of staff, phones Olivier and says Wynne is "going to have to make a decision around the appointment," later telling him they should chat about what he would be interested in doing, be it "appointments to boards or commissions," a constituency office job or role in the party executive.

Dec. 15: Olivier goes public with claims that Lougheed and Sorbara offered him a job or appointment to step aside; Progressive Conservatives ask Ontario Provincial Police to investigate; New Democrats ask Elections Ontario to investigate.

Dec. 16: Thibeault publicly announces he will be the Ontario Liberals' byelection candidate.

Jan. 7: Wynne calls Sudbury byelection for Feb. 5; sends letter to riding association president and nomination commissioner informing them of Thibeault's appointment.

Jan. 12: OPP conclude no criminal offence was committed by the Liberals.

Jan. 15: Olivier releases audio of his conversations with Lougheed and Sorbara; Progressive Conservatives ask OPP to reopen the investigation.

Feb. 5: Thibeault wins Sudbury byelection; in a court document filed in order to get Olivier's original recordings, police say they have "grounds to believe" a criminal offence was committed. The investigation is ongoing.

Feb. 19: Elections Ontario makes "unprecedented finding" that Lougheed and Sorbara's actions were in "apparent contravention" of the Election Act; matter is referred to OPP and federal Crown.