They don't have authority for non-WEI.

US v. Davis, 482 F. 2d 893, 913 (9th Cir. 1973) "a screening of passengers and of the articles that will be accessible to them in flight does not exceed constitutional limitations provided that the screening process is no more extensive nor intensive than necessary, in the light of current technology, to detect the presence of weapons or explosives, that it is confined in good faith to that purpose, and that potential passengers may avoid the search by electing not to fly."

Agreed with by every court to consider it, and reflected in current TSA policy statements.

Juice is obviously not dangerous, whether in 2oz, 50oz, or 5 gallons. TSA is quite capable of distinguishing juice from WEI. QED.

To put it more simply, there are two basic questions IMO:

1. Should TSA be allowed to refuse to screen liquids that are properly presented for screening, and within TSA's capability to screen, unless TSA first makes a medical determination of necessity?

2. Should TSA be allowed to refuse travel to someone on the basis of items that have been screened and cleared as not WEI?

Remember, I'm not objecting to them screening it. They're welcome to screen my liquids, so long as they don't damage them in the process, which their current screening policies do not risk. To the contrary, I insist that they screen it — and that I be allowed to travel with things that have passed screening, without interrogation or medical determinations made by people who have no business doing so.