Umm in my opinion I started to take notice and question the media's motives when I first saw the stories that Bush was literally being blamed for allowing Katrina to happen because he was racist.
That was my awakening point and since then I've noticed it becoming increasingly partisan to today, where it has openly become the ministry of progressive propaganda.
Watergate, is literally 1 day of Clinton's life. The most notorious scandal wouldn't even register when compared to a week with Hillary. But it's ignored by the media