The media seem to be interpreting this case as something that could eliminate federal agencies' ability to write regulations at all. Are they exaggerating?
IMO, yes they are exaggerating.
The argument against
Chervon is not about authority or ability to write regulations. Writing regulations involves a fairly strict notice and comment process and authority to write them is given by statute.
Chevron deference is about agencies (a) interpreting their own authority to write regulations and (b) interpreting the meaning of statutes and properly enacted regulations.
In our world, I guess we can point to the super-broad way the FAA has defined "compensation" as something "bad" that
might not be there in a non-Chevron world. Of course, we can also point to the entire body of "non-regulatory" FAA guidance, including the AIM and the ACs. Literally every big advance we've seen in the RNAV/GPS world is "interpretation," neither "statute" nor "regulation." What if deciding that it was OK to use GPS in lieu of VOR required 6 month to a year of regulatory activity?
But getting rid of
Chevron does not even mean the end of interpretations and non-regulatory guidance. Without getting into the weeds, its about what happens when a regulation or or interpretive guidance is
challenged. How is it tested for legality? Pure
Chevron deference comes down to, "so long as an agency interpretation is
rational, it will be upheld." Without Chevron, it just means that challenges would be measured by a different standard.
That's what I think all the cases which have limited Chevron have done - changed what can be challenged and how. And, while I could be wrong, that's all I really see coming out of this case. The decision will be to either uphold or reject the National Fisheries requirement that fishing boats pay federal observers. The decision may be reached by articulating a new standard of deference - what type and how much.