From WNYC in New York, this is NPR's On the Media.

Bob Garfield is away this week. I'm Brooke Gladstone.

Army intelligence analyst Bradley Manning is accused of leaking an ocean of classified material to the self-styled whistleblower site, WikiLeaks.

It's the biggest leak of classified documents in U.S. military history.

He's now the subject of the Obama administration's fourth known leak investigation,

a record number for any White House. Shane Harris, senior writer for Washingtonian magazine,

says that despite this president's expressed commitment to transparency, his White House is uncommonly zealous in its pursuit of leakers.

Shane, welcome to on the media.

Hi, it's good to be here. Thanks.

First off, can you bring us up to date on the investigation of the WikiLeaks leaker?

If he is found guilty of the charges, he's going to face the potential of a very, very long prison sentence.

Sources I've talked to about this have also said that the FBI could get involved.

Who else has this White House prosecuted?

Well, they're currently prosecuting a man named Thomas Drake, who was a senior executive at the National Security Agency.

And he is accused of leaking classified information to a reporter

named Shavon Gorman for the Baltimore Sun. They've also successfully got a guilty plea from a

former contract linguist for the FBI. Investigators are also currently investigating who

leaked information about a CIA operation from many years ago to the New York Times reporter

James Reisen. Mr. Reisen's actually been subpoenaed now for a second time to appear before a

grand jury and to identify his source. Is this Justice Department trying to make an example of

James Reisen? He has really made a career on exposing some really sensitive classified operations.

So there are people in the career elements of the Justice Department that would very much

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