Did Mueller rely on the dossier for any criminal charges?

No. The special counsel investigation led to indictments of 34 people and three companies. Many of those indicted — like Mr. Kilimnik — reside abroad and have not faced trial. Mr. Mueller obtained nine guilty pleas or jury convictions, including half a dozen close Trump associates. None of those indictments cited the dossier as evidence.

The fact that Mr. Mueller did not obtain sufficient evidence to charge Trump associates with conspiracy is subject to disputed interpretations that overlap with the debate over the dossier’s significance. Trump supporters frame the lack of conspiracy charges as proof there was no collusion. By combining this with the false premise that there would not have been any Russia investigation without the Steele dossier, they portray Mr. Trump as a victim of a hoax.

Beyond pointing out that there is a range of cooperation and coordination that falls short of the legal definition of “conspiracy,” Trump skeptics argue that Mr. Mueller never definitively got to the bottom of what happened in part because of Mr. Trump’s efforts to impede the investigation — like dangling a pardon before Mr. Manafort to keep him from cooperating.