The public owns the spectrum
Yes, the public owns the spectrum. Privates license it for use. And such licenses come with stipulations. The January 2011 waiver came wirth strict coinditions with regards to interference with GPS, conditions that do not look liek they have any chance of being met. The recent petition to try to get the FCC to rule that GPS is entitled to no protections with regards to that spectrum has been seperated from the waiver issue by the FCC (prudent move), and the public comment period is expected for petitions of this kind. They can petition to try have a declaration that GPS cuases cancer if they like, it is their right, but that does mean there is any chance in hades that the FCC will agree.
As for GPS listening into that spectrum, there is no law agaisnt that. If GPS users wanted to stampedee pink rhinos into that spectrum it is not up to the licensee to prohibit it. And the FCC has not ever prohibited GPS from listening into that spectrum. Cry all they want, they do not "own" the spectrum, the public does.