The important decision is In re Grand Jury Subpoena Duces Tecum Dated March 25, 2011. From the opinion by Judge Tjoflat:
We hold that the act of Doe’s decryption and production of the contents of the hard drives would sufficiently implicate the Fifth Amendment privilege. We reach this holding by concluding that (1) Doe’s decryption and production of the contents of the drives would be testimonial, not merely a physical act; and (2) the explicit and implicit factual communications associated with the decryption and production are not foregone conclusions.
First, the decryption and production of the hard drives would require the use of the contents of Doe’s mind and could not be fairly characterized as a physical act that would be nontestimonial in nature. 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. Continue reading
A Colorado judge this week ordered a woman to decrypt her laptop so that law enforcement officials could use the information against her in a pending fraud case.
“I find and conclude that the Fifth Amendment is not implicated by requiring production of the unencrypted contents of the Toshiba Satellite M305 laptop computer,” Judge Robert Blackburn wrote in his decision. […] In the course of the investigation, the FBI executed search warrants on Fricosu’s home and seized her Toshiba Satellite M305 laptop, among other devices. Upon inspection, however, they discovered that the device was encrypted, barring the agents access to its contents.
Fricosu has refused to provide the password to her computer, asserting her privilege against self-incrimination under the Fifth Amendment.
In reaching his decision, Judge Blackburn referenced the case of Sebastien Boucher, who was arrested in December 2006 when he and his father tried to cross the Canadian border into Vermont. Border officials found child porn on his computer and confiscated the device, but when they tried to access it later, it was password-protected. By December 2007, a Vermont federal judge ruled that Boucher could not be forced to reveal his computer password and incriminate himself.
On appeal, however, a grand jury required Boucher to produce a decrypted version of his hard drive, not the password. With this workaround, constitutional rights are not violated, the jury found, because the contents of the device “are a foregone conclusion…”
via Judge: Order to Decrypt Laptop Does Not Violate Fifth Amendment | News & Opinion | PCMag.com.