Sanders Campaign's Voter Data Access Issue 'Resolved'

A campaign spokesperson for Democratic presidential candidate Bernie Sanders said staffers today regained access to voter data from the Democratic National Committee, which had earlier blocked the campaign's access, prompting the Sanders campaign to sue the DNC.

The resolution was later confirmed by the Democratic National Committee in a statement.

"The Sanders campaign has now complied with the DNC's request to provide the information that we have requested of them. Based on this information, we are restoring the Sanders campaign's access to the voter file, but will continue to investigate to ensure that the data that was inappropriately accessed has been deleted and is no longer in possession of the Sanders campaign. The Sanders campaign has agreed to fully cooperate with the continuing DNC investigation of this breach."

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Clinton campaign spokesman Brian Fallon said in a statement Saturday morning the campaign was "pleased" the Sanders camp had agreed to the independent audit.

"We expect further disciplinary action to be taken as appropriate," he added.

The Sanders campaign had earlier filed a breach of contract lawsuit against the Democratic National Committee after it blocked the campaign's access to voter data, leaving the candidate's team "hamstrung" and losing "critical fundraising and publicity opportunities," according to legal documents.

"The voter data is vital to the fundraising and voter identification efforts of all presidential candidates," the suit, filed in Washington DC federal court, says, estimating costs that "exceed $600,000.00 per day."

"The DNC should not be permitted to tip the scales of the Democratic presidential primary without clear justification and contractual cause," the documents say.

The DNC had temporarily suspended the campaign's use of the database for the time being after Sanders staffers accessed data from the Clinton camp during a breakdown of the firewall in the system.

The database includes information such as demographic and geographic data for registered voters and voter history and is vital to the Sanders campaign because it "has been financed primarily with contributions from individual donors rather than Political Action Committees," the suit says.

According to the documents, on Dec. 16, the company that administers the database, NGP VAN, "released a modification" that "contained a critical security flaw that allowed the [Sanders] Campaign and other presidential campaigns to view Confidential information disclosed by competing campaigns."

"Before the Bug could be resolved, several staff members of the Campaign accessed ad viewed Confidential information," the documents say. One "may have repeatedly accessed" the information and was fired, according to the suit, which seeks at least $75,000 in damages.

The next afternoon the DNC "suspended or terminated" access to the data without written notice, the documents say.

"The DNC may not suspend the Campaign's access to critical Voter Data out of haste or desperation to clean up after the DNC's own mistakes," the document say.

The head of the DNC, Rep. Debbie Wasserman Schultz, said the committee's lawyers are reviewing the suit and intend to restore the campaign's access after Sanders' team provides a full accounting of what happened.

"A the end of the day, we are one Democratic family," she said.

But she said she said it was "baffling to me that they would be hurling accusations with us" that the Sanders camp would accuse them of being in cahoots with Clinton.

She called the accusations, "completely unfounded."

"This was a very egregious breach and our data was stolen," Clinton campaign manager Robby Mook said. "This was not an inadvertent glimpse into our data. It was not as the Sanders campaign has described it 'a mistake.'"

Stu Trevelyan, CEO of NGP VAN, said in the company immediately began an audit and had not had a problem in its 19-year history.

"The one area that was impacted was voter file data," Trevelyan said in a statement obtained by ABC News. "We are confident at this point that no campaigns have access to or have retained any voter file data of any other clients; with one possible exception, one of the presidential campaigns. NGP VAN is providing a thorough report to the DNC on what happened and conducting a review to ensure the integrity of the system."

"We immediately began an audit to determine if any users had intentionally or unintentionally gained access to data they normally would not have access to. And determined that only one campaign took actions that could possibly have led to it retaining data to which it should not have had access," Trevelyan said.