I agree both that TSA is limited to WEI, and that evidence of how they treat liquids at checkpoints would go to prove lots of it — e.g. (a) whether the policy is in fact limited to WEI, (b) whether there has ever been any liquids WEI intercepted at a checkpoint, and (c) whether my proposed policy, which would significantly reduce the harm to passengers (both with & without disabilities), would in any way harm the security of transportation.

My point was narrow: a "reasonable person" question is either subjective (i.e. about that person's individual state of mind), or an application of law to facts (e.g. for objective reasonableness). I can ask about the latter in requests for admission. Asking about the former is more limited, however, since it'd be hard to get evidence of it outside of interrogatories & depositions — and not relevant except for the people involved in the incident.

(ETA: … and for the TSA itself. I can depose the agency per se as to what "it" thinks, using a 30(b)(6) deposition. I intend to do that too, of course, but that's going to be one of the very last things, once I have a ton of evidence to use to pin them down.)

Obviously I do intend to depose the people involved, and asking them about their subjective beliefs is going to be part of those depositions.

However, the vast majority of discovery is document production. If I can identify it, it already exists, it's not privileged, and it's related, I can probably get my hands on it. Which is why I rephrased your suggestion into documents I can ask for.

Thanks!