The Washington Post reported late Thursday night that the senator's campaign had breached voter data from the Hillary Clinton campaign, prompting the Democratic National Committee to suspend the Sanders campaign's access to its voter file. In a Friday press conference, Sanders campaign manager Jeff Weaver threatened to sue the DNC if its access to the file wasn't promptly restored.
"If the DNC continues to hold our data hostage, and continues to try to attack the heart and soul of our campaign, we will be in federal court this afternoon seeking an immediate injunction," Weaver said.
Meanwhile, DNC Chairwoman Debbie Wasserman Schultz defended the suspension, telling MSNBC on Friday, "They are prohibited from accessing another campaign's proprietary information, and we have the ability to suspend that campaign's access to the voter file in order to make sure that we can preserve the integrity of the voter file and ensure that there is confidence in it."
Given the voter database's importance, managed by the firm NGP VAN, in making crucial campaign decisions, the suspension marked a devastating setback for the Sanders campaign, which will need a robust field operation to surmount the Clinton financial juggernaut.
Since news of the breach broke, critical new details have emerged about the Sanders campaign's conduct and how it came to light.
The latest: In a statement provided to Mic on Friday morning, Sanders spokesman Michael Briggs indicated that "the staffer" behind the breach had been fired late Thursday. The staffer has since been identified as data director Josh Uretsky, who told CNN that he'd done nothing improper.
"We knew there was a security breach in the data, and we were just trying to understand it and what was happening," Uretsky said. "To the best of my knowledge, nobody took anything that would have given the (Sanders) campaign any benefit."
While Uretsky said he was only trying to investigate a software error in the NGP VAN system, Bloomberg Politics reports that NGP VAN learned of the error from "a third party," not the Sanders campaign. What's more, Bloomberg says that on Wednesday morning, the Sanders camp created and saved 24 lists using the voter data.
But Weaver said Friday afternoon that the campaign had learned of the breach two months ago and promptly "contacted the DNC and told them about the failure."
"We were concerned that our data could be compromised and we were assured at the time the firewall would be restored," Weaver said.
In Weaver's telling, the breach fit a larger pattern of "incompetence" on NGP VAN's part.
"On more than one occasion, they have dropped the firewall between the data of competing Democratic campaigns," he said. "This is dangerous incompetence."
In a statement Friday, NGP VAN said that it "immediately mobilized our engineers to investigate the source of the issue" on learning of it Wednesday morning. The statement made no mention of previous breaches.
Weaver was no less harsh in his assessment of the DNC's decision to suspend Sanders' access to voter data, and promised swift legal action if the decision isn't reversed.
The Clinton campaign did not immediately respond to Mic's requests for comment.