We don’t know exactly what Mueller has on Trump or what he will do with it. Much of what we do know, however, is hard to credit to a careful observance of the law, from the $130,000 that Trump paid to Stormy Daniels in a convoluted scheme to buy her silence to the Trump Tower meeting between top Trump campaign personnel and Russian operatives. Meanwhile, many (but surely not all) of Trump’s efforts to obstruct the investigation into his campaign, including his firing of James Comey as FBI director, are haplessly public.

Would any observer of Trump’s slapdash history, in politics as in business, be shocked if Mueller wrote a factual “road map” every bit as detailed and damning as the one Jaworski produced on Nixon?

And if Mueller does, then what? In that case, Pelosi and her allies may have to choose between the happy work of partisanship and the more fraught demands of constitutional obligations. Given the recalcitrance of Senate Republicans, who are highly skilled at rebuffing calls to conscience, Pelosi is unlikely to want to impeach Trump only to see the effort falter. But a full accounting from Mueller could make impeachment look less like bad politics, and more like grim duty.