Justin Trudeau has been handed a live grenade as he enters the critical period to retain office. We might wonder: what might he do? Thumb into the hole? Toss it down the road?

He has no easy call. The report last Wednesday by the federal ethics commissioner into the SNC-Lavalin affair is in living memory the most extensive critique of a handling of a conflict-of-interest scandal of any prime minister.

Beyond that, its implied questions about possible obstruction of justice are the most troubling for any prime minister. Further, its consequences - either for an election outcome or for the definition of the Liberals under Trudeau - could be the most substantial single albatross for any prime minister that anyone can recall.

So, what will Justin do?

His first response is, without question, the most banal of any possibility.

Found by an impartial officer to have interfered with his attorney general, implied to have made attempts to obstruct the natural course of prosecution, then castigated for denying that independent officer vital information and free-speaking witnesses, what did he do?

Up to the microphone he went, defending his actions as defending jobs, as if nothing in the leadership playbook of a prime minister might supersede that - not leaving his attorney general alone, not leaving his public prosecution office free to decide if a trial were merited, not standing back as SNC-Lavalin paid a price for paying off Libyan officials for years to earn contracts.

The report from commissioner Mario Dion is frightening. Its verbiage about Trudeau’s efforts toward his then-attorney general was clear: “circumvent,” “undermine,” “discredit.” If cynics believe Trudeau is merely the first prime minister to be caught in what others have tried and done, then we are a sad lot indeed. Regardless, we are to worry.

Dion articulated the scandal as best he could - nine witnesses had to tell him that they had relevant information but couldn’t disclose it due to cabinet confidences, a matter Trudeau sealed and wouldn’t unseal in what the prime minister promised would be a full review.

What is clear is that the Quebec engineering firm, since shellacked to a shell of its former self, lobbied for prosecutorial changes through legislation to permit it - and, yes, possibly, others down the road, but for the time being it and it alone - to defer trial through an agreement that would not render a judgment that might disqualify it from federal contracts or deliver some kind of corporate scarlet letter.

Trudeau bought the line, biting into the hook with its sinker, and determined that thousands of Quebec jobs – the kind that mean more than, say, the Alberta energy ones – might be lost if the company were torpedoed by a trial.

We know the rest of the story: Jody Wilson-Raybould, his justice minister and attorney general, received a steady stream of entreaties from Trudeau’s team to overturn her prosecution service’s decision to proceed to trial; the prime minister’s office kept asserting that her service’s decision might be best reviewed by more eminent jurists, the ones that might back its viewpoint; she bowed up but eventually bowed down to Trudeau’s withering verdict she could not keep her gig, winding up in a lesser role; news leaked of the episode; she and cabinet colleague Jane Philpott stood firm, spilled some beans, and were smacked from caucus.

Today Wilson-Raybould is favoured to retain Vancouver-Granville as an independent.

Justin? Well, as he moves into the campaign for October’s election, he is not so favoured to retain his job. One might write off Dion’s report as one of those inside-baseball things that do not affect voters. One might very well be proven wrong, though, because the handling speaks to the culture that the prime minister and his crew created. Adversaries will make a meal of it.

If he wishes to get past it, he has to summon a better defence than he has to date. If he is sincere and accepts responsibility for what happened, and agrees that it shouldn’t have happened that way, then he needs to abandon his protect-jobs-at-any-cost nonsense.

His job is to demonstrate principled leadership, not blind power.

Given that SNC-Lavalin has in recent weeks restructured, changed its focus to stick more to its original knitting of stewardship of engineering projects, and shown its senior management the door, there is little for him to lose now in acknowledging that he was protecting a mirage.

The cliched phrase about what he might do is called ripping the bandage off the scab. Yes, prime minister, it hurts, but the fresh air that greets it ultimately heals.

Kirk Lapointe is a columnist with the Prince George Citizen.