Robert Mueller’s investigation into ties between Russia and the Donald Trump campaign maneuvers mostly in secret. But the infamous dossier at the heart of the scandal, which was compiled by ex-British spook Christopher Steele on behalf of an intelligence firm alternately retained by the conservative Web site Washington Free Beacon and members of the Clinton campaign, constantly finds its way to the center of the news.

First there was Monday’s juicy Foreign Policy story revealing that BuzzFeed, which published the dossier in early 2017 and was subsequently sued over it, recently commissioned “a team led by a former top F.B.I. and White House cybersecurity official” to trek all over the world “on a secret mission to verify parts” of the explosive document. Now, BuzzFeed is taking the Democratic National Committee to court in an attempt to compel it to turn over information it believes will bolster its defense against Aleksej Gubarev, a Russian business magnate who says he was libeled in the dossier when it tied him to the Russians’ alleged hacking of the D.N.C.’s e-mail servers. In a nutshell: BuzzFeed believes the D.N.C. has information that could show a link between Gubarev and the e-mail hacking, which would undercut his libel claim. “We’re asking a federal court to force the D.N.C. to follow the law and allow BuzzFeed to fully defend its First Amendment rights,” a BuzzFeed spokesperson wrote in an e-mail.

BuzzFeed’s motion asserts that the D.N.C., citing privacy concerns, has been unwilling to comply with a subpoena for that information. As BuzzFeed’s lawyers argue: “The material requested from the D.N.C.—which amounts only to the digital remnants left by the Russian state operatives who hacked their systems—is highly relevant to Defendants’ ability to establish the truth of the allegedly defamatory claims about them in the Dossier. And the D.N.C. has identified neither privilege nor burden that would prevent them from complying with the Subpoena.” In legal papers, the D.N.C. has argued that disclosing the digital signatures, supposedly left by the Russia-directed hacking organizations known as Cozy Bear and Fancy Bear, would inevitably expose details of the D.N.C.’s information systems, possibly making them more vulnerable to another hack. (A D.N.C. spokeswoman did not immediately have a comment late Tuesday afternoon.)

BuzzFeed maintains that its decision to publish the dossier was justified because a number of the document’s claims have subsequently been corroborated. And since that’s the bedrock of its defense, the publication is committed to trying to collect as much evidence as possible in support of that argument. Back in September, as I reported at the time, BuzzFeed filed a motion against the F.B.I. to depose former F.B.I. Director James Comey and former director of national intelligence James Clapper—the idea being that if Comey or Clapper were to testify, it would confirm under oath that the dossier was being discussed at the highest levels of government, and was therefore of interest to the public. BuzzFeed will be in court in Washington on Thursday for a hearing related to that matter.