WASHINGTON – Hillary Clinton is coming under pressure, as federal investigators question her top aides about the private email scandal that is haunting the former Secretary of State’s campaign for the presidency.

Clinton is still reeling from news that her former staffer Bryan Pagliano’s emails are not in the possession of the State Department. Pagliano, who installed Clinton’s private server, pleaded the Fifth Amendment to avoid self-incrimination in the growing criminal investigation.

“The Department has searched for Mr. Pagliano’s email pst file and has not located one that cover the time period of Secretary Clinton’s tenure,” a State Department spokesman said Monday. Pagliano’s missing emails are raising transparency alarms among observers of the case.

“The whole thing stinks to high heaven,” said Dan Metcalfe, the founding director of the Office of Information and Privacy within the Department of Justice and onetime chief DOJ official for overseeing Freedom of Information Act (FOIA) matters.

As 147 FBI agents work on the investigation, Clinton’s top aide Cheryl Mills is feeling the heat. Mills and her attorney reportedly left her interrogation by the FBI, regrouped, and later came back when the FBI went off script. According to the Washington Post:

Mills and her lawyer left the room — though both returned a short time later — and prosecutors were somewhat taken aback that their FBI colleague had ventured beyond what was anticipated, the people said…

The questions that were considered off limits had to do with the procedure used to produce emails to the State Department so they could possibly be released publicly, the people said. Mills, an attorney herself, was not supposed to be asked questions about that — and ultimately never was in the recent interview — because it was considered confidential as an example of attorney-client privilege, the people said.

Clinton has yet to be called by investigators.

It’s now been nine months since Breitbart News broke the story that Clinton had multiple classified “Top Secret” emails on her private server, and that she had classified emails on her homebrew server that were classified when “originated.” As America waits to find out if the FBI will recommend indictment, and whether the Department of Justice under Loretta Lynch will indict, the case against Clinton seemingly grows more solid.

The case hinges on whether or not Clinton violated the Espionage Act of 1913 (18 U.S. Code & 793 subsection f) by possessing national defense information and allowing it “through gross negligence permits the same to be removed from its proper place of custody or delivered to anyone in violation of his trust, or to be lost, stolen, abstracted, or destroyed.”

Here are key pieces of evidence that could lead to a whole lot of trouble for Hillary Clinton:

Exhibit A: The Non-Secure BlackBerry

Hillary Clinton used a BlackBerry to send and receive classified emails during her time as Secretary of State, even though her device was so non-secure that she wasn’t even allowed to use it in her “Mahogany Row” offices on the seventh floor of the State Department.

Clinton did not get her BlackBerry from the Department. It appears that her aides Huma Abedin and Cheryl Mills actually did get their devices from the Department, but those devices were destroyed. The State Department testified in a civil court filing:

“[The State Department] does not believe that any personal computing device was issued by the Department to former Secretary of State Hillary Clinton, and has not located any such device at the Department…

…Because the devices issued to Ms. Mills and Ms. Abedin would have been outdated models, in accordance with standard operating procedures those devices would have been destroyed or excessed.”

Now here’s where the BlackBerry issue really becomes important. Clinton was warned in 2009 to stop using her BlackBerry because her device suffered a security “vulnerability” when she visited East Asian countries, including China, on her first official State Department trip.

On March 11, 2009, a State Department official, whose name is redacted, sent an email to another State Department official, whose name is redacted. That email, obtained in a lawsuit by Judicial Watch, might be the smoking gun in the Hillary Clinton email case – at least as it pertains to Clinton possibly losing information due to “gross negligence.”

According to the official, Hillary Clinton approached Ambassador Boswell and asked him about BlackBerry use. Specifically, Clinton asked about the fact that the Department had “intelligence concerning the vulnerability during her recent trip to Asia.”

The official wrote:

After this mornings “management meeting” with the A/Secys, Secretary Clinton approached Ambassador Boswell and mentioned that she had read the IM and that she “gets it.” Her attention was drawn to the sentence that indicates we (DS) have intelligence concerning this vulnerability during her recent trip to Asia.

Secretary Clinton has asked Ambassador Boswell for this information. Please prepare a short informal paper OR provide the A/Secy with a briefing on this matter. Your assistance is appreciated. The Secretary did not provide a “due date”…BUT the Ambassador would like to close this loop as soon as possible.

But Clinton continued to use her BlackBerry as late as 2011, two years after this warning, according to former State Department official Wendy Sherman. Sherman spoke Clinton’s BlackBerry use in a speech that was quietly recorded on video and released right before the Iowa caucus, which Clinton barely won over Bernie Sanders.

Exhibit B: White House Less Than Supportive

The Obama White House’s refusal to go to bat for Clinton publicly during this ordeal has been one of the most intriguing narratives of the election. Though President Obama helped her out a bit by saying that he didn’t think Clinton jeopardized national security, the Obama operatives who still remember the vicious 2008 primary season aren’t doing her any favors.

Senior White House adviser Valerie Jarrett dropped a relevant bombshell when she said that the White House sent official guidance to Clinton telling her to use a government email account. Clinton’s decision to ignore the White House’s warning does not bode well for her defense against the “gross negligence” portion of the Espionage Act.

Remember that brief, bizarre stretch of the campaign right around the February 1 Iowa caucus when Clinton was going out of her way to say nice things about Obama? That might not have been just a ploy to make her seem more electable than Bernie Sanders. It might have also been a ploy to protect her own legal interests by cozying up to a man with pardon power who oversees the Department of Justice.

“She wants to get protected. That’s the only reason she’s nice to him,” Trump said of Clinton’s relationship with Obama.

Exhibit C: Russian Hackers

Clinton’s server was highly vulnerable to attack, including the kind that occurred to several of her email contractors and could have happened to her when she opened a virus-infected email from her friend.

Clinton confidante Neera Tanden, president of the Center for American Progress, sent Clinton a summer 2011 email with a spam link and the lines “Look what I’ve found” and “Here is a very nice offer. Enjoy!”

In her reply, Clinton indicated that she opened the spam link.

“Neera–did you send me this? If not, I think your email address book has been hacked. If so, why? Anyway, hope you’re well,” Clinton wrote back to Tanden.

On at least five documented occasions, Clinton received emails in her personal inbox that came from hackers, including hackers from Russia as part of a scheme in which victims’ personal data ended up getting sent to foreign computers including in Russia.

Here’s another very important piece of the puzzle: In September 2011, Clinton’s inbox was reviewed by outside IT professionals as part of a formal analysis of the security of her private email account. Those IT professionals found that Russian hackers had at least repeatedly attempted to get into Clinton’s information.

Why did Clinton have IT experts in to review her email account just weeks after Tanden sent her “hacked” email to Clinton?

One thing is clear: if those Russian hackers did gain entry to Clinton’s information, they would have had a field day. Why? It turns out Clinton’s server had an open webmail portal that gave potential hackers unrestricted access to Clinton’s personal information.

Exhibit D: She Avoided Signing Non-Disclosure Form

As Breitbart News exclusively reported, Hillary Clinton did NOT sign a mandatory OF-109 “Separation Statement” when she left the State Department.

That statement would have required her to affirm that she had returned all classified materials in her possession. Clinton’s top aide Cheryl Mills also avoided signing a separation statement.

Citizen researcher Larry Kawa provided to Breitbart News the most clear-cut evidence that Clinton avoided going through mandatory channels to return classified government information.

Clinton signed a “Classified Information Nondisclosure Agreement” on January 22, 2009. This document is known as an SF-312. It is standard for government employees to sign an SF-312 when they begin working in a role that gives them access to classified information. But she was also required to sign an OF-109, or “Separation Statement,” when she left the job.

That OF-109 document would have required her to affirm the following:

I have surrendered to responsible officials all classified or administratively controlled documents and material with which I was charged or which I had in my possession. I am not retaining in my possession, custody, or control, documents or material containing classified or administratively controlled information furnished to me during the course of such employment or developed as a consequence thereof…

But Clinton never signed an OF-109, even though the State Department Foreign Affairs Manual requires all employees to do so.

A Separation Statement exists for top Clinton aide Cheryl Mills, and a copy of it was quietly released by the State Department. But the statement was never signed, by Mills or anyone else.

It was left blank.

Exhibit E: The Clinton Foundation

Breitbart News reported that Clinton’s server was operating on the same email network, and was housed in the exact physical space, as the server for the Clinton Foundation, indicating that they were sharing a server. That space was in New York City, not in the basement of Clinton’s Chappaqua, New York, home, as she claimed. Daughter Chelsea Clinton’s office was also using the email network.

Numerous Clinton Foundation employees used the clintonemail.com server for their own email addresses, which means that they were using email accounts that, if hacked, would have given any hacker complete access to Hillary Clinton’s State Department emails, as well.

No wonder then that the FBI expanded its investigation to scrutinize possible public corruption on the part of the Clinton Foundation. And no wonder then that Rep. Marsha Blackburn asked the Federal Trade Commission (FTC) to review the Clinton Foundation’s charitable status.

Exhibit F: Server Went Down Three Times

Clinton’s server went down at least three times during her tenure as secretary of state, including weeks after the Benghazi terrorist attack. Clinton never even told her own IT Help Desk at the State Department that she was using a private server, keeping them in the dark about her activities.

Furthermore, Clinton went so far as to hide the identity of the people running her private server, paying a company called Perfect Privacy, LLC. That company, based in Jacksonville, enters its own meaningless contact information into official Internet databases so that its clients’ identities will not be exposed.