Department of State officials refused to identify to a congressional committee the “chain of custody” – the complete list of people who had access to former Secretary of State Hillary Clinton’s private email server, according to The Daily Caller News Foundation’s investigation.

The request was made last spring by the House Select Committee on Benghazi probing the 2012 terrorist attack on the U.S. Consulate in which Ambassador Christopher Stevens and three other Americans were murdered.

The chain of custody evidence is essential to determining if Clinton or people close to her violated federal laws on handling of classified materials.

In a private meeting earlier this year between the State Department, Clinton’s representative and Benghazi committee staff, the committee asked State to identify the “chain of custody” of people who “touched” or otherwise had access to Clinton’s email and to additional copies, according to a knowledgeable congressional source.

The materials were sought “in order to identify those persons who had touched them and then for us to determine who might have violated classified handling procedures. And we got nothing,” the source said.

In a related development Monday, a federal judge with the U.S. District Court for the District of Columbia ordered an accelerated hearing for Aug. 20 on whether to order discovery by attorneys for Judicial Watch on the State Department’s possession of Clinton’s servers, accounts, hard drives or other devices.

U.S. District Court Judge Emmet Sullivan ordered the State Department to respond no later than Wednesday to the non-profit watchdog’s request for discovery following repeated failures by the government to fulfill its obligations under the Freedom of Information Act.

Judicial Watch has filed multiple FOIA requests concerning Benghazi and the Hillarymail scandal. If the non-profit government watchdog is granted discovery, it would create many more potential legal problems for Clinton. She remains the leading candidate for the 2016 Democratic presidential nomination but recent polls suggest the scandal is deeply undermining her credibility.

The “chain of custody” issue is important as federal officials have confirmed that at least 300 or more emails on Clinton’s server contained highly sensitive classified material and at least two were stamped “Top Secret,” the highest classification level within the intelligence community.

The Top Secret designation means information disclosed in that category “could be expected to cause exceptionally grave damage to the national security,” according to Executive Order 13526, a December 2009 national security order signed by President Barack Obama.

As more is disclosed about the server or servers, the circle of people who came in contact with Clinton’s emails grows larger by the day.

In addition to close Clinton aides with access to her Chappaqua, N.Y., home where the private server was located, the committee is focusing its attention on attorneys from the Williams & Connolly law firm where David Kendall is “of counsel.”

Kendall is a long-time Clinton lawyer and confidante who represents the former secretary of state on the email server investigation.

Clinton gave Kendall a thumb drive with more than 30,000 State Department emails. He reportedly instructed his staff to review the thumb drive and print out hard copies for the department.

“We do know it was Kendall’s subordinates — the names for which we do not know — who did that search. But we don’t know who they are to this day,” the congressional source said.

Kendall has previously received various levels of clearances, most recently as the lawyer for former CIA Director David Petraeus, who pled guilty to mishandling classified materials by sharing documents with a mistress who was writing a book.

Petraeus could have received prison time but was sentenced to two years’ probation.

Kendall has maintained that he enjoyed a security clearance because of his work with Petraeus, but the congressional source told TheDCNF that, “I’d be floored if the attorneys had it for the review.”

Senate Judiciary Committee Chairman Chuck Grassley told Kendall in a letter made public Monday that “it appears the FBI has determined that your clearance is not sufficient to allow you to maintain custody of the emails.”

The Iowa Republican noted that Kendall received the emails in December 2014, but it was only in May of this year that the State Department delivered a classified materials-certified safe to store the thumb drives.

After it was disclosed that “Top Secret” classified information was on the hard drive, Kendall was ordered to build a Sensitive Compartmented Information Facility, or SCIF, at Williams & Connolly. A SCIF is a hardened room with very secure restrictions for access.

Grassley added, “since at least May 2015 and possibly December 2014, it appears that in addition to not having an adequate security clearance, you did not have the appropriate tools in place to secure the thumb drives.”

Other parties may have had unauthorized access to the Clinton materials if Kendall printed out the emails using either a commercial printing company or an unsecured Williams & Connolly copier machine.

To print out 30,000 paper emails, “it seems likely that [Kendall] would have contracted a commercial printing firm and then as a result, that has now been exposed to someone else,” observed Alex McGeorge, the head of threat intelligence at Immunity, Inc.

Even if Williams & Connolly printed out the 30,000 emails in-house, the best copiers are really computers with large storage capacity that would keep the classified information, McGeorge said.

The committee is also looking at Platte River Networks, a small IT company in Colorado that was under contract to upgrade and maintain Clinton’s server in July, 2013. TheDCNF reported Friday that Platte River was not certified by the Defense Department to handle classified materials.

Andy Boian, a spokesman for Platte River, confirmed in an interview Monday with TheDCNF that the backup Platte River driver was in New Jersey, not Colorado, but he refused to divulge further details.

Boian claimed the company is not the target of an investigation by the FBI or the Department of Homeland Security.

The highly sensitive nature of the material was confirmed by the inspector general for the Intelligence Community last month.

The IG, I. Charles McCullough, found at least two emails were classified “Top Secret/SI/TK/NOFORM.”

SI stands for “Special Intelligence,” meaning it was the product of an intercepted communication. TK represents “Talent Keyhole,” confirming the communication or image was obtained by satellite.

In court papers filed last Friday with U.S. District Court Judge Rudolph Contreras, the State Department conceded that as intelligence officials undertook a new review of Clinton’s emails, as many as 305 were identified as falling under some form of classification.

Jed Babbin, a former undersecretary for Defense under President George H. W. Bush, said the SI/TK classification is one of the highest clearances within the U.S. government and requires special approval.

“The stuff we’re talking about is SI/TK. It doesn’t matter if you have the clearance or not. You have to be cleared into the specific part of intelligence to do that.

“This is really, really serious,” he said, if it was “divulged to the public or to an enemy power they would be most likely to severely damage the United States. Not just to damage the United States. It would severely damage the United States. So this is big.”

TheDCNF contacted both the State Department and Kendall’s office seeking comment. Neither responded to our inquiries.

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