House Speaker Paul Ryan's call to keep Hillary Clinton away from classified information in the wake of her email server inquiry looks to be largely toothless, according to former federal officials with experience in the intelligence community.

The Wisconsin Republican on Wednesday sent a letter to Director of National Intelligence James Clapper requesting that he deny the presumed Democratic presidential nominee access to any classified information during the rest of the 2016 campaign. His appeal came after FBI Director James Comey on Tuesday said his agency was not recommending charges against Clinton for her use of a private email server that handled classified information while secretary of state – guidance the Justice Department followed on Wednesday by formally closing its Clinton email probe.

Clinton will begin receiving intelligence briefings on the state of the world and national security threats once she is officially made the Democratic presidential nominee at the party's convention later this month, a tradition dating back to 1952.

Despite not recommending charges, however, Comey said Clinton and her staff were "extremely careless" in managing sensitive information and that people who engage in similar behavior are "often subject to security or administrative sanctions."

In his letter to Clapper, Ryan said denying "Clinton access to classified information certainly constitutes appropriate sanctions." Senate Republicans also reportedly plan to introduce legislation prohibiting Clinton and anyone involved with her email server from receiving security clearances.

But regardless of Republicans' protestations, there is no one agency that allows or denies access to classified government information across the board and could accordingly deny Clinton her briefings. And while government agencies make security clearance decisions regarding employees, Michael Vatis, founding director of the FBI's National Infrastructure Protection Center, says "nominees do not receive a security clearance from an agency the way an agency employee or contractor would."

Meanwhile, members of Congress can receive government briefings without need for a clearance, says Tony Cordesman, former director of intelligence assessment in the Office of the Secretary of Defense.

"The U.S. gives background briefings all the time throughout government to people who don't have a security clearance," says Cordesman, now with the Center for Strategic and International Studies. But "even if you have a security clearance, there is a wide range of information people won't have access to."

Presidential nominees like Clinton, for instance, could receive classified information without details about the source or methods used to gather the data, Cordesman says. Presumptive Republican nominee Donald Trump also could receive less detail about classified information because he has not previously been a government official.

Agencies have different filters for data and standards to provide access to classified information, so "there is no one size that fits all," Cordesman says.

"Elected officials who are appointed to positions like intelligence committees are trusted by their colleagues and have a need to receive more classified access than, say, people on the education committee," he says

It is unclear how Clinton's colleagues, staffers or people who communicated with her via exchanges on her private server will be reviewed for secure government access.

However, the president has the power to overturn a decision made by the Executive Office of the President to reject a security clearance, according to The New York Times . So if Clinton were elected, she could ensure former colleagues receive access to jobs there.

Completing a recent background check for a previous government job also counts favorably during the clearance process when people switch federal agencies, says Vatis, now a partner at the Steptoe & Johnson law firm.

"When government employees switch agencies, their new agencies are supposed to honor the background investigation that was performed on the employee at her first agency, without needing to do a whole new investigation," he says. "However, some agencies with access to particularly sensitive information such as the CIA and FBI may require their own, new investigation."

The government standard is to reinvestigate clearances every five years, although a clearance can be revoked at any time, says Jack Langer, spokesman for House Intelligence Committee Chairman Devin Nunes, R-Calif.