WASHINGTON — For nearly two weeks last year, the FBI operated what it described as one of the Internet’s largest child pornography websites, allowing users to download thousands of illicit images and videos from a government site in the Washington suburbs.
The operation — whose details remain largely secret — was at least the third time in recent years that FBI agents took control of a child pornography site but left it online in an attempt to catch users who officials said would otherwise remain hidden behind an encrypted and anonymous computer network. In each case, the FBI infected the sites with software that punctured that security, allowing agents to identify hundreds of users.
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Lawyers for child pornography victims expressed surprise that the FBI would agree to such tactics—in part because agents had rejected them in the past—but nonetheless said they approved. “These are places where people know exactly what they’re getting when they arrive,” said James Marsh, who represents some of the children depicted in some of the most widely-circulated images. “It’s not like they’re blasting it out to the world.”