Is interpretation left strictly up to FAA Legal (meaning experienced attorneys) or is there something left to inspectors charged with enforcing the statutes? I ask because of the "letter" versus the "spirit" of the law and how it can be interpreted by different authorities with different results.
You may get some differing opinions on this (so what's new?) but here's my take.
Ultimately it's the job of Legal to make the interpretations - whether by letter opinion or by pushing for an interpretation when representing the FAA in a certificate or civil penalty action - assuming it's not in one of those special and narrow categories ("arbitrary, capricious, or otherwise not according to law") where the NTSB can substitute its own view.
But Legal is not the only source or even the only official source of how to apply the FAR (application necessarily involves some interpretation). Find an Order, AC, an AIM provision or some other similar FAA-published source to support your view in a certificate action and you have a pretty good argument that a contrary interpretation being pushed by the FAA should be disregarded.
But even outside of that, I think that anyone who thinks that Legal just looks at the words on the paper and makes stuff up without input is mistaken (even though some of the opinions do sound that way). When it comes to requirements for certificates and ratings, I'm with Ron that Legal will try to defer to Flight Standards - they, not Legal are the experts in that area. And that will hold true for a lot of stuff.
I think inspectors are in a different category altogether - they are police officers - specialized police officers, but police officers nevertheless. If an inspector wants to start a certificate action against a pilot using an FAR that the inspector interprets in a certain way, I'm sure the attorney assigned to the case will look at it closely, but will ultimately see how it fits with the rest of the rules, existing interpretations, etc. I wouldn't want a FSDO inspector given the power to make the rules read the way he wants to any more than I'd want the cop on the beat deciding what constitutional rights a protester has. The relation between the inspectors and Legal is probably a lot like the relationship between the police force and the DA's office.
I like to think that part of the role of Legal is to filter those things. In addition to being contrary to existing interpretations, one of the problems I saw in the FAQ was that it tended to be very result-oriented. Lynch would decide what he wanted the FAR to mean, and then twisted things around so it would (usually adding that there was no "regulation, reason, or common sense behind an opposite view). The problem was that if you applied his "reasoning" to other situations, it broke down. I like to think that Legal has a broader view of the "fit" of interpretations. That's part of what they should be doing, although sometimes you wonder...
It would be interesting to know what the history behind the recent "known icing" debacle was. Was this a case where the Eastern Region just made something up based on existing cases without a clue about flying? Was there input from an inspector who figure it would make his job easier and was looking for a result instead of the consequences of the decision? Was it some combination? Or something completely different?
Beats me.