There has always been pressure on the media from the White House. It is one of the most coveted reporting assignments among the press in DC. Mess up too much and press credentials can be removed. Nixon, who hated the press, even had a list of the most-hated reporters. And those were the days before massive corporate ownership.
And with corporate ownership comes the corporate philosophy, and sometimes, if you don't agree with their political bent as an editor or reporter, don't let the door hit you on the way out.
And twisting a story is very easy, just by placement of the facts. Candidate X was arrested for a drug charge 30 years ago. Support X and you bury that fact at the bottom of the story; support the opponent and that ends up usually in the first three paragraphs.
Many of the media will do their best to bring out all the facts, but then there all other elements at play.