POST NOTE – there are two corollaries to this story. Considering:
A. The state-secrets / state-security / whistle-blowing / publication “rights” issue.
B. The use of “terrorism” legislation as an expedient or indirect justification for actions re A.
C. The stop and search “suspicious” individuals in response to B.
1. The Miranda case is fundamentally about A, where B is simply an expedient, a non-issue.
2. The real issue with B is C, and what counts as suspicion. At one extreme, every time any individual comes into (otherwise routine) contact with police or security officials there is a statistically random sampling of all of us. (I get stopped for a possible parking / driving offence – or as happened recently, I draw a police officer’s attention to a nearby argument turning ugly – and one in x times, I’m invited over to the office for a thorough security search?) Or the other extreme, each official is subjectively allow to pick up on “appearances” at that point, given time available to their primary job. What do I look like, who am I with, what does my behaviour suggest, where have I just come from, etc. Particularly tricky where your primary job is rights vs aliens at border control. (A pure red-herring in the Miranda case, where the individual was pre-identified, beyond any immediate “suspicion”.)
Once you bring in pre-existing “evidence” concerning an individual’s security interests / activities, the contentious question is not really about the evidence itself, but about discovery of evidence – “surveillance” based on wide general selection or on subjective / circumstantial suspicion “prior to any actual evidence” – interest has to start somewhere. (Common problem in the whole “scientific” agenda here is what counts as reasonable evidence for …. whatever decision / action next.)