The marine mixed stock fisheries were the first nail in the coffin currently being prepared for Chinook. Those were the fisheries that reduced adult age at maturity and consequently reduced adult size.

The short answer is that AK and Canada wield the power. AK does what it wants and nobody in the lower 49 have the horsepower to stop them. Plus, nobody else harvests AK salmon except under their direction. Canada can and does over harvest southern US stocks in order to get the US's attention and get AK off of Canada fish.

Because of the size of the AK/Canada catches that are "not controllable" there are instances where NOAA has established "Recovery Exploitation Rates" for some Chinook stocks down here where RERs are greater than estimated MSY escapement. Meaning that if we fish at the "Recovery Rate" we drive those stocks to extinction. This really isn't a secret, just nobody talks about it much.

The PSC Commissioners are appointed by the Federal Governments. There are some specific requirements as to who has to represented on the Commission and Panels.