Why the FBI’s request is so significant from a forensics point of view:

…What many haven’t considered is the significant difference — in the legal world — between providing lab services and developing what the courts will consider an instrument.

An instrument is the term used in the courts to describe anything from a breathalyzer device to a forensics tool, and in order to get judicial notice of a new instrument, it must be established that it is validated, peer reviewed, and accepted in the scientific community. It is also held to strict requirements of reproducibility and predictability, requiring third parties (such as defense experts) to have access to it.

In other words, were the courts to follow Zdziarski’s line of thinking and interpret the FBI’s request as one to produce an “instrument”, there truly is no guarantee of secrecy and in fact a burden of public peer review.