Prime Minister Stephen Harper has a new political opponent to contend with heading into the 2015 election, one that has the potential to inflict more significant damage than Tom Mulcair or Justin Trudeau.

Former Conservative Sen. Mike Duffy will have his day in court on 31 charges ranging from bribery to breach of trust in relation to a host of alleged misuses of public funds.

The legal proceedings will unfold in the run-up to the next federal campaign scheduled for the fall of next year, keeping the details alive in the headlines. His first court date is scheduled for the day after Parliament reopens in September.

How much Harper knew about the clandestine $90,000 payment made by his former chief of staff Nigel Wright to Duffy to cover his contested Senate expenses is likely to come up. The courts are reluctant to call prime ministers while Parliament is sitting, but that won’t preclude the defence from making a very public attempt to have him testify.

Others, including Harper’s former leader in the Senate, Marjory LeBreton, the current Conservative Fund chairman Irving Gerstein, the PM’s former legal counsel and other close aides including Wright could also figure prominently in the legal to-and-fro.

The details of how Duffy was called upon to campaign alongside Conservative candidates during the 2011 election, while allegedly claiming both business and Senate expenses, will also be laid out.

The situation is reminiscent of the one faced by Liberal Prime Minister Paul Martin, who contended with the fallout from the sponsorship scandal and a federal inquiry during the 2004 and 2006 elections.

Harper now, like Martin then, says he had no knowledge of the scheme at the heart of the scandal. An important factor in Harper’s favour is that the RCMP did not lay charges against Wright.

Still, both Duffy and the opposition will try to keep Harper in the scandal’s orbit.

If Duffy’s dramatic public denunciations of Harper and his closest officials on the floor of the Senate last fall are any indication, the former broadcaster will not hold anything back in defending himself.

“It will all come out in due course when all of the players are under oath and the email chain can be seen in its entirety,” Duffy foreshadowed during his speech on Oct. 22.

Duffy’s lawyer, Donald Bayne, has also exhibited a certain elan in defending his client publicly, suggesting the blame lies with Conservative officials and senators.

Duffy has alleged he was threatened and coerced by the prime minister’s office and Conservative senators into repaying $90,000 worth of contested Senate living expenses, even though he felt he had not broken any rules.

“To date, Sen. Duffy has never had a fair hearing, either in the Senate or in the media,” Bayne said in a statement late Wednesday.

“We are confident that when the full story is told, as it will be, and shown to be supported by many forms of evidence, it will be clear that Sen. Duffy is innocent of any criminal wrong-doing.”

The opposition parties quickly seized the opportunity Thursday to directly link the Duffy charges with Harper himself. Both the NDP and the Liberals said the saga is about Harper’s lack of judgment.

“We’re hopeful these charges will help answer the questions the prime minister has refused to answer: What did he know, and when? Why hasn’t the prime minister taken corrective action for the behaviour of his top advisers and members of this caucus?” said Liberal foreign affairs critic Marc Garneau.

“When will those involved in the PMO coverup be fired and face ethics investigations, rather than to be shuffled to other senior posts in government?”

The Prime Minister’s Office issued a statement Thursday distancing itself from Duffy, who has been suspended from the Senate, along with two other former Conservatives appointed by Harper.

“We have assisted the RCMP throughout their investigation, and congratulate them on the progress they have made,” said spokesman Jason MacDonald.

“Those who break the rules must suffer the consequences. The conduct described in the numerous charges against Mr. Duffy is disgraceful. As this is now a criminal matter that is before the courts, we have nothing further to add.”