Say you get arrested, your computer is seized and state wants to peek at the encrypted data hidden away on your machine's hard drive. Can it force you to decrypt your computer? Traditionally, the answer has been no: courts have previously ruled that ordering a defendant to decrypt their data was tantamount to self-incrimination -- a violation of their 5th amendments rights. The Massachusetts Supreme Court sees things differently, and has recently ordered a defendant to decrypt his machine because the pertinent data's presence on the computer was a "foregone conclusion." In other words, if the police already know the data they are looking for is there, it doesn't count as new testimony and is not protected by the 5th amendment.