By Arshad Mohammed and Jonathan Allen
WASHINGTON (Reuters) - The FBI's harsh criticism of Hillary Clinton's use of a private email system as U.S. secretary of state could make it difficult for some of her closest aides to keep or renew government security clearances, but it would not affect Clinton herself if she is elected president, experts said.
Federal Bureau of Investigation Director James Comey said on Tuesday an FBI investigation had found evidence that Clinton, now the presumptive Democratic presidential candidate, and her aides "were extremely careless in their handling of very sensitive, highly classified information" at the State Department.
Comey said he would not recommend that the Justice Department bring criminal charges - a recommendation accepted by Attorney General Loretta Lynch on Wednesday - but the FBI director noted that people found to have been similarly careless often face consequences in the form of "security or administrative sanctions."
Most administrative sanctions, anything from a reprimand to a dismissal, can't be imposed on Clinton and three of her closest aides Cheryl Mills, Jake Sullivan and Huma Abedin as they have already left government, experts of the government's classified information regime said.
But legal experts said that if Clinton aides were found to have treated classified material with extreme carelessness that could give the government reason to consider denying them a security clearance in the future or suspending or revoking one they may currently have.
"If the system is fair and equitable, then they should all have difficulty maintaining or obtaining a security clearance in the future," said Mark Zaid, a Washington D.C.-based attorney who specializes in national security matters.
Steven Aftergood, a Federation of American Scientists expert on national security and classification policy, noted, however, that Comey had highlighted what he called a problematic security culture at the State Department. "So it might be hard to penalize individuals for this episode if their entire agency embraced similar practices," Aftergood said.
A Justice Department spokesperson declined to elaborate on Comey's statement, which did not name any of the aides. The Clinton campaign did not respond to questions about the security clearances of Clinton, Mills, Sullivan and Abedin, nor did lawyers for the three aides.
Abedin, who has been a personal aide to Clinton for about 20 years, and Sullivan, Clinton's policy director at the State Department, sent information the government now says is classified to Clinton's unauthorized private email account, according to email records released by the State Department.
It remains unclear if they sent any of the 110 emails that Comey said contained information that was classified at the time they were written. The only author of such emails he identified was Clinton herself.
A small number of other department colleagues sent information the government has since marked as classified to Clinton's account less frequently, the records show. The government forbids handling classified government secrets outside secured channels it controls. Clinton has said she did not knowingly send or receive classified information through her private email server.
Both Abedin and Sullivan now hold senior roles in Clinton's presidential campaign and are widely expected to join a Clinton administration if she is elected on Nov. 8.
Mills, who also passed along information the government now deems classified, has continued to work as a lawyer for Clinton but has no formal role in the campaign. It unclear if she will seek a role in a Clinton administration.
Some presidential appointments require Senate confirmation, and lawmakers could use any past criticism of an aide’s handling of government secrets as a reason to block their appointment to a Senate-confirmed job, said William J. Leonard, a former director of the federal government's Information Security Oversight Office.
The State Department declined to discuss individual cases and said that as a matter of policy it does not publicly disclose who has a security clearance. But it said it can apply security sanctions, such as putting a black mark on a person's permanent personnel file that would come up in future background checks, even against former employees.
For those former officials who maintain an active security clearance, they could lose it.
"Department policy is to maintain files on personnel who are found to have mishandled information to guide current and potential future decisions about employment and security clearances," John Kirby, a department spokesman, said in a statement.
Without knowing precisely what the FBI found about the actions of specific Clinton aides, it is impossible to say what effect there may be on their current or future security clearances.
Paul Ryan, the House Speaker and the most senior elected Republican official, said on Wednesday that Clinton should be denied the security clearance required to receive the customary intelligence briefing that government officials give to presidential nominees before the election.
Presidents and other elected national officeholders are not required to have background checks to receive government secrets, according to experts and the Central Intelligence Agency.
"It would roil our system of representative democracy if a security official could say that the president ... can't have a security clearance," said McAdoo Gordon, an attorney with extensive experience in security clearance matters.
(Reporting By Jonathan Allen and Arshad Mohammed, editing by David Rohde and Ross Colvin)