A federal magistrate is reversing course and ordering a Wisconsin man suspected of possessing child pornography to decrypt hard drives the authorities seized from his residence.

The development comes as a month after the same magistrate thwarted prosecutors' demands that Jeffrey Feldman unlock drives they believe contain child pornography.

Decryption orders are rare, but are likely to become more commonplace as the public slowly embraces a technology that comes standard even on Apple computers. The orders have never squarely been addressed by the Supreme Court, despite varying opinions in the lower courts.

Just last month, U.S. Magistrate William Callahan Jr. said the Fifth Amendment right against compelled self-incrimination protected even those suspected of unsavory crimes, but added that "this is a close call."

But prosecutors convinced Callahan to change his mind. Among other reasons, the authorities were able, on their own, to decrypt one drive from Feldman's "storage system" and discovered more than 700,000 files, some of "which constitute child pornography," the magistrate said.

When he ruled against the government last month, the magistrate said the authorities did not have enough evidence linking Feldman to the data, and that forcing the computer scientist to unlock it would be tantamount to forcing him to confess that it was his. But that theory is now out the door, because the data on the decrypted drive contains pictures and financial information linking Feldman to the "storage system," the magistrate said last week.

"Such being the case, the government has now persuaded me that it is a 'foregone conclusion' that Feldman has access to and control over the subject encrypted storage devices. Thus, under the current state of the law as more particularly discussed in the court's April 19 Decision and Order, Fifth Amendment protection is no longer available to Feldman with respect to the contents of the encrypted storage devices."

Contrast that to what the magistrate ordered last month:

This is a close call, but I conclude that Feldman’s act of production, which would necessarily require his using a password of some type to decrypt the storage device, would be tantamount to telling the government something it does not already know with 'reasonably particularity' —namely, that Feldman has personal access to and control over the encrypted storage devices. Accordingly, in my opinion, Fifth Amendment protection is available to Feldman. Stated another way, ordering Feldman to decrypt the storage devices would be in violation of his Fifth Amendment right against compelled self-incrimination. (.pdf)

The government told the magistrate that the "FBI is performing admirable" (.pdf) in its quest to pick hard drive locks. But it needs an encryption order because "the expense in time and resources investigating cases like this one is beginning to inhibit the provision of justice."

Feldman was not immediately reachable for comment.

Among the last times this came up in court was last year, when a federal appeals court rejected an appeal from a bank-fraud defendant who has been ordered to decrypt her laptop so its contents could be used in her criminal case. The issue was later mooted for defendant Romano Fricosu as a co-defendant eventually supplied a password.

The authorities had evidence linking her to the hard drive. They had recorded a jailhouse conversation between her and a co-defendant, in which the laptop's contents were discussed, according to court papers.

Meanwhile, a failure to comply with the decryption order might result in a contempt charge, landing Feldman in jail pending compliance. Alleging you forgot your password presents a host of other legal issues.