I don't really understand how people can claim any newscaster is "trustworthy" or "untrustworthy." A large percentage of the news they present during each broadcast was neither researched, gathered nor fact checked by them personally, so if it is accurate it is no thanks to them.
This idea never occurred to the person who gave 'Uncle Walter" the sobriquet as "The most trusted man in America."
Now, print journalism is where trustworthiness comes in because bylines tell you who is responsible for making sure what is reported is accurate.
Ask Jayson Blair or Janet Cooke if that is a fail safe method.