They are still going through clinical trials its just that getting to that stage has been accelerated.

So this isn't like we are relying on AZ to create it, test it and sign it off. National agencies will ultimately sign off on whether it can be used or not. Given the high profile nature of this vaccine you can be sure that results will be widely studied, and the opportunity to hide results they don't like will be limited given we all know the trials are occurring.