A federal appeals court has ruled it improper to compel a child pornography suspect to decrypt his hard drive because such an act would violate his Fifth Amendment rights.
The ruling (PDF) by the Atlanta-based US 11th Circuit Court of Appeals in the case of an unnamed suspect from Florida (known in court papers as "John Doe") goes against US legal thinking in previous cases where courts held a person ought to be obliged to turn over encryption codes or passwords in a criminal investigation.
The appeals court ruled that: "[the] Fifth Amendment protects [the man’s] refusal to decrypt and produce the contents of the media devices", the Wall Street Journal reports.
The US Fifth Amendment holds that no one "shall be compelled in any criminal case to be a witness against himself". But this protection against self-incrimination only goes so far.
Supreme Court rulings have previously found that a subject can be compelled to turn over a key to a safe containing potentially incriminating evidence, but is not obliged to supply the combination to a safe to investigators. US law is less clear on how this applies to encrypted files on computers (which might be considered akin to digital safes).
The US 11th Circuit Court of Appeals ruling goes against two district court cases on whether the government can compel subjects of investigation to turn over either the passphrase or a plain text version of the data held on an encrypted drive.
In the case heard by the 11th Circuit Court of Appeals, the suspect allegedly refused to supply the passphrases for five of his laptop hard drives and five external hard drives. His hard drives had been seized by police at the time of his arrest in a hotel room in October 2010, and encrypted using TrueCrypt, the court documents said.
The suspect refused to supply the passphrase in time for his appearance before a federal grand jury in Florida last April, the WSJ reported, and continued to refuse to do so in response to a later court order requiring him to decrypt the hard drives. A federal judge held the suspect in contempt of court but the appeal court overturned this ruling.
“We conclude that the decryption and production would be tantamount to testimony by Doe of his knowledge of the existence and location of potentially incriminating files; of his possession, control, and access to the encrypted portions of the drives; and of his capability to decrypt the files,” wrote Judge Gerald Bard Tjoflat, one of the three judges hearing the appeal, in the ruling (PDF).
The ruling continued: “It is not enough for the Government to argue that the encrypted drives are capable of storing vast amounts of data, some of which may be incriminating. Just as a vault is capable of storing mountains of incriminating documents, that alone does not mean that it contains incriminating documents, or anything at all.”
The Vermont case, which came before the courts in 2009, also involved child pornography but authorities in that case said they already had evidence that the suspect's drive contained child abuse material before they requested the courts to order the suspect to supply the passphrase for an encrypted portion of the disk.
In the Florida case, all the drives are fully encrypted and the police have no certain knowledge of what they contain.
In January, a federal judge in Colorado ordered a woman charged with fraud to hand over decryption keys to her computer. A regional appeals court rejected her appeal, and she was ordered to decrypt the information last week.
The Electronic Frontier Foundation filed representations on behalf on the defence in both the Florida and Colorado cases.
In a statement, the EFF welcomed the ruling in the Florida case. "The government's attempt to force this man to decrypt his data put him in the Catch-22 the 5th Amendment was designed to prevent – having to choose between self-incrimination or risking contempt of court," said EFF senior staff attorney Marcia Hofmann. "We're pleased the appeals court recognised the important constitutional issues at stake here, and we hope this ruling will discourage the government from using abusive grand jury subpoenas to try to expose data people choose to protect with encryption." ®