Full disk encryption is too good, says US intelligence agency

The study, titled “The growing impact of full disk encryption on digital forensics,” illustrates the difficulty that CSI teams have in obtaining enough digital data to build a solid case against criminals.

The paper does go on to suggest some ways to ameliorate these issues, though: Better awareness at the evidence-gathering stage would help, but it also suggests “on-scene forensic acquisition” of data, which involves ripping unencrypted data from volatile, live memory (with the cryogenic RAM freezing technique, presumably).