Democratic presidential candidate Hillary Clinton and key aides are vulnerable to three felony charges and one misdemeanor count under the Espionage Act because of the unauthorized transfer of classified documents to her private email server, former national security and law enforcement officials tell The Daily Caller News Foundation.

As many as 150 FBI agents are deployed on the case and FBI Director James Comey and Attorney General Loretta Lynch are reportedly meeting twice weekly to discuss the progress of the investigation.

The FBI is reportedly in the “final stages” of its probe and working closely with members of the Department of Justice’s National Security Division to decide if a prosecution goes forward.

On Jan. 14, I. Charles McCullough III, inspector general for the intelligence community, revealed of the 1,000 classified documents found on Clinton’s server, about two dozen are Top Secret and SAP materials. SAP documents are higher than the Top Secret classification and contain the nation’s most sensitive secrets.

Former law enforcement and intelligence officials contacted by TheDCNF agree if there is wrongdoing, it is likely prosecutors will focus on the classified documents.

The most serious charges are felonies cited in Title 18 of the U.S. Code of the Espionage Act in sections 793, 798 and 1001. Experts contacted by TheDCNF say these could serve as the foundation for any criminal prosecution of Clinton or her aides.

Section 793 applies to anyone who has been “entrusted” with information relating to the national defense. The law applies to a federal official who “through gross negligence permits” information “to be removed from its proper place of custody or delivered to anyone in violation of his trust, to be lost, stolen, abstracted or destroyed.”

Section 798 applies to any government official who “knowingly and willfully communicates” information “to an unauthorized person.” Section 1001 addresses giving “false statements.”

Clinton and her aides also could be charged under section 1924, which is a misdemeanor. This was the April, 2015, charge former CIA Director David Petraeus negotiated with prosecutors for sharing classified information with a mistress who also served as his biographer.

But the felony charges loom large. “A federal prosecutor would naturally focus first on the most serious allegations: willfully transmitting or willfully retaining Top Secret and Compartmented material using a private server system,” says retired Brig. Gen. Kenneth Bergquist who also served as an assistant attorney general at the Justice Department.

“The prosecutor’s charging document would likely include felony counts under 18 U.S. Code, Section 793 and under 18 U.S. Code Section 798 against each transmitting individual as well as separate counts against each receiving and retaining individual,” he told TheDCNF.

Ronald T. Hosko, who enjoyed a 30-year career in the FBI and served as the bureau’s assistant director for its criminal division until 2014, agrees. He particularly looks at Section 793.

“This certainly applies to those who would take classified materials and move it to an unauthorized server in an unauthorized location, in this case to her [Clinton’s] house,” he told TheDCNF.

“The prohibited conduct is the unsecured transmission of highly classified information,” to Clinton’s server, “as well as the receipt and retention of highly classified information in an unapproved manner,” says Bergquist.

“As a former career senior intelligence officer and special operations special mission intelligence officer and National Security Council staff member, I believe it is inconceivable that if it is verified that Hillary Clinton’s server contained or had SAP information on it that she could possibly escape indictment and criminal prosecution,” adds retired Col. James Waurishuk, a 30-year veteran in the national security field.

Hosko notes Section 1001 also could be invoked by prosecutors, which addresses giving “false statements.”

When federal officials leave office, they sign documents that “in effects say, ‘you can’t take any state secrets with you.’” The document states the federal official is signing it under the penalty of perjury.

“You wonder, did she knowingly and intentionally sign it, knowing full well ‘all my records are going with me,’” asks Hosko.

Clinton aides Cheryl Mills, Huma Abedin and Jacob Sullivan may be very vulnerable to charges.

Waurishuk told TheDCNF “Staff aides like Huma Abedin, Cheryl Mills, etc. had absolutely ‘zero’ reason to have any access to any SAPs, period. How that happened and who authorized it is criminal in itself.”

Hosko says the espionage act sections pertain to “having knowledge that materials were illegally removed from its proper place” and it also is a crime if one “fails to make prompt report of such loss to his superior.”

“Does that apply to those circle of aides who were involved in the transmission of this sensitive information? On the surface it looks like the answer is ‘yes,’” says Hosko.

[dcquiz] Penalties for Espionage Act felonies involving federal officials who “knowingly remove classified material without the authority to do so and with the intention of keeping that material at an unauthorized location” are up to one year and $1,000. Petraeus was fined $100,000 for his misdemeanor case.

If the removal makes classified information available “to an unauthorized person,” the fines escalate to $10,000 and 10 years in prison. The penalties increase to 15 years per count if any the disclosure of information identifies a covert agent.

Intelligence officials have charged that Clinton’s home-brew server was hacked by foreign intelligence agencies, divulging an unknown amount of intelligence information to foreign governments, including HUMINT, which is human intelligence that can cover covert agents.

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