OTTAWA -- The curtain is poised to rise on the opening act of what's sure to be the most politically charged courtroom drama to play out in Ottawa in many years.

Sen. Mike Duffy's first court date is scheduled for Tuesday morning, although the larger-than-life senator is not expected to attend in person.

The ensuing trial could have major repercussions for Prime Minister Stephen Harper and his Conservative government ahead of next year's federal election campaign.

One central question looms over the trial: how much did Harper know about the secret $90,000 payment made by his former chief of staff Nigel Wright to cover Duffy's contested Senate expenses?

The prime minister on many occasions has insisted that he knew nothing of the plan to repay Duffy's expenses.

Duffy faces 31 criminal counts related to his expense claims, which stem from his Senate housing and travel charges and the $90,000 payment from Wright.