Here we have what I think is a display of an intelligent mind specialized in one area, funded by a state institution, and weak at resolving moral conflicts. Computer scientists (and any self-respecting scientists) HAVE to separate their ethics from the interests of state institutions. Phrases in the paper resembling something like "where the cryptographer has a duty to serve the public and keep their self-interest in check" indicate this.
I've read a paper recently on designing systems to have security exceptions for law enforcement and calling them "exception requirements" or something to that effect. This is the sort of thing a good study of ethics can help to resolve.