CIA 'mistakenly' destroys copy of 6,700-page US torture report

Per Snowden:

"I worked @CIA. I wrote the Emergency Destruction Plan for Geneva. When CIA destroys something, it's never a mistake."

https://twitter.com/Snowden/status/732991012340137988

> last summer CIA inspector general officials deleted an uploaded computer file with the report and then accidentally destroyed a disk that also contained the document.

How the hell does one accidentally destroy a disk? Are we talking a hard disk or a DVD?

Which is more believable? An organisation whose charter is to gain, analyse, and make use of information:

a) Deleted the document despite having extensive procedures for proper document handling, or

b) Is lying* about deleting "the only copy"

*Lying - mostly as a form of manipulation - is literally part of the job description for intelligence agencies.

Who actually believes a)? :(