How attorneys in alleged Russian troll factory case plan to keep Mueller secrets from Moscow

After more than a year of arguing, prosecutors and defense attorneys in a court case related to alleged Russian interference in the 2016 presidential election have agreed on a complex system for handling "sensitive" discovery information, designed to ensure the government’s best-kept secrets stay far from the Kremlin as the 2020 election looms.

So far, defense attorneys for Concord Management and Consulting, a Russian firm accused of funding a troll factory that aimed to sow discord before and after the 2016 election, have not been able to share – or discuss -- the sensitive information with officers of the company under a strict protective order, which the defense attorneys said makes it virtually impossible to prepare for trial.

Prosecutors, on the other hand, said that revealing the sensitive information to individuals in Russia, far beyond the reach of U.S. legal jurisdiction, could compromise national security and potentially reveal to the Russian government just how much U.S. intelligence and law enforcement knows -- and doesn’t know -- about Russia’s purported interference efforts in 2016. The U.S. government says Concord is controlled by Yevgeny Prigozhin, a co-defendant in the case and an associate of Russian President Vladimir Putin.

"That information, used by a foreign adversary, could be used to avoid detection in the future," U.S. Attorney Jonathan Kravis told the court in March, echoing concerns national security and legal experts shared with ABC News in October.

After months of haggling, on Wednesday the two sides offered the judge a joint proposal for a compromise: the government would identify some sensitive materials, called "intermediate Sensitive," that can be taken to Russia and seen there by certain court-authorized individuals, like company officers or potential witnesses in the case, as long as they view the materials in a designated location in Russia and are escorted by an authorized chaperone, according to the new protective order that's been proposed.

But the most closely held information, dubbed "U.S. Sensitive," would remain in the U.S., locked away in the law offices of Reed Smith, the American firm representing Concord. To share that information with anyone, Concord’s attorneys would first have to get the court’s permission, potentially by going through a third party called a "firewall counsel" which would review the request. Filings related to the request would be done electronically but also delivered by hand on an "encrypted disk."

If approved, those people would still have to physically come to the U.S. to view the material. Defense attorneys for Concord have previously said there’s little chance company officers, some of whom like Prigozhin are co-defendants in the case, would travel to the U.S. for fear of arrest upon arrival.

"U.S. sensitive material may under no circumstances be disclosed, transported, or transmitted outside the United States unless so ordered by the Court," the proposed order says.

The discovery in the case is made up of millions of documents, including the material already deemed non-sensitive, and ranges from social media postings to email messages. Eric Dubelier, the lead defense attorney, said in a pre-trial hearing Tuesday that his legal team has spent a year trying to through all the information and still isn’t done sorting through it.

The sensitive information, Wednesday’s filing says, includes witness statements, information that could identify potential witnesses, information related to ongoing investigations and information "related to sensitive law enforcement or intelligence collection techniques."

Prosecutors have indicated they’re especially concerned about information contained in search warrants executed by law enforcement in the case.

U.S. District Judge Dabney Friedrich has yet to sign the new protective order as of this report, but indicated in court Tuesday she was eager to review it.

Concord is the only one of three Russian business entities and 13 Russian individuals charged in the case to respond in court. U.S. law allows for a corporate defendant to fight a court case without any individual from the corporation physically being in court – and, in this case, without putting themselves in danger of being arrested.

Concord has pleaded not guilty to a conspiracy charge, and the trial is tentatively scheduled to begin in April 2020. Russia has long denied election interference allegations.

In the meantime, special counsel Robert Mueller, who’s 448-page report included a long section on Russia’s alleged online influence operation ahead of 2016, warned that Russia will be back for 2020.

"They’re doing it as we sit here," he told lawmakers in July. "And they expect to do it during the next campaign."