The Clintons have paid “hundreds of thousands of dollars” to cover the legal bills for a Bill Clinton aide who sits at the center of the FBI’s investigation into Hillary Clinton’s private email server.

That’s according to Washington Times opinion editor Monica Crowley who reports in a new column that a knowledgeable source tells her that the Clintons are covering legal expenses for Justin Cooper, a longtime aide to the former president.

Such an arrangement would raise questions over whether the Clintons are paying Cooper’s bills in order to ensure that they have some oversight of his interactions with federal investigators. It would also raise questions about whether the Clintons are paying other aides’ legal costs.

Cooper registered clintonemail.com in his own name on Jan. 13, 2009. That email domain is the same one Hillary Clinton exclusively used to send work-related emails as secretary of state. Emails sent on that account were stored on a server that the Clintons kept at their personal residence in New York.

According to Crowley, Cooper’s role in helping set up Clinton’s mysterious email arrangement has put him in the FBI’s cross hairs. She reports:

A source familiar with Mr. Cooper’s arrangement with the Clintons tells me that they have paid his legal fees associated with the FBI investigation, amounting to “hundreds of thousands of dollars.” They aren’t paying those costs out of a sense of decency. They’re paying them because he knows the “why” of the server, which may very well have been to make it easier for the foundation to hustle big donations. One wonders what, if anything, Mr. Cooper is telling the FBI — and whether the whole sordid Clinton house of cards will be left standing.

The FBI seized Clinton’s server last year after it was determined that some of her emails contained classified information. And now, investigators are reportedly poised to interview aides who have knowledge about the system.

And according to a Fox News report from earlier this year, the FBI’s investigation has expanded to a public corruption probe which centers on the intersection of the Clinton Foundation and State Department.

Cooper could also be embroiled in that aspect of the investigation, according to Crowley, who also works as a Fox News analyst.

The little-known Cooper has worked for the Clinton Foundation and Teneo Holdings, a consulting firm with close ties to the Clintons. Along with Doug Band — Bill Clinton’s former “body man,” a former counselor to the Clinton Foundation, and a co-founder of Teneo — Cooper kept in contact with Clinton’s State Department aides, emails from Clinton’s account show. One of those aides is Huma Abedin, who served as Clinton’s deputy chief of staff while also working for Teneo.

The overlap has raised questions over whether the Clinton Foundation and Teneo were using access to the State Department to help raise money and attract clients.

The possibility that the Clintons are paying legal bills for aides embroiled in the FBI investigation has already been broached by Congress.

Senate Judiciary Committee chairman Chuck Grassley has asked lawyers for the Clintons and Abedin — as well as for former Clinton aides Cheryl Mills, Philippe Reines, and Jake Sullivan — if they have entered any “joint defense agreements.”

The Iowa Republican has asserted that such arrangements could pose conflicts of interest because they would help ensure that the Clinton insiders refrained from providing evidence that could be detrimental to the Clintons.

The lawyers have refused to say if those arrangements have been made.

Grassley has also asked whether the Clintons are covering legal costs for Bryan Pagliano, the former information technology specialist who set up and managed Clinton’s private email server. But Pagliano’s lawyer, Mark MacDougall of the Clinton-connected law firm Akin Gump, has also refused to say if such an arrangement is in place. Pagliano has since entered an immunity deal with the FBI in exchange for his cooperation in the investigation.

Some evidence has emerged suggesting that the Clintons are paying legal bills for those embroiled in the email fiasco.

[dcquiz] In October it was reported that the Denver-based IT company that handled Clinton’s server after she left the State Department had submitted an invoice to Clinton seeking payment for legal and public relations expenses. (RELATED: Senator Wonders If Hillary Is Covering Legal Expenses For Tech Firm That Managed Email Server)

The company, Platte River Networks, had control of Clinton’s server when it was turned over to the FBI. It billed Clinton’s accountant, Marcum LLP., nearly $50,000 for legal and PR expenses.

The Clinton campaign and the Clinton Foundation did not respond to The Daily Caller’s requests for comment.

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