Subject: Re: Ain't That The Truth
If a known liar says 2+2=4, that's a true statement. Somebody on a jury who doesn't know that adding 2 and 2 to get 4 would be prejudiced against that witness, however (which is why that tactic is used).

Again, you're conflating a mathematical statement - which is an abstract statement that is testable irrespective of context - with reporting of facts. If a known liar says 2+2=4, you can determine the truth of that statement without relying on the testimony of the liar. But if a witness says "I heard a gunshot at 9:45 p.m. and saw the defendant leave the building two minutes later," you can't determine the truth of that statement without taking into consideration whether you believe the witness or not. If that witness is a known liar, or is shown to have impaired vision, or was drinking at the relevant time, or has memory problems, or has a personal relationship with the defendant (or a victim), or any of a number of other factors.....you might not believe them. You can't determine "the truth" without making an assessment of the credibility of the source - because you don't have independent ways of testing the truth of the proposition apart from the fact that the source made the claim.

That's not prejudice. You have to form an assessment of the credibility of a source if the only method you have of determining the truth of a proposition is that the source asserted it.

Hence Walter Cronkite's reporting not being much different from John Chancellor's, say. Was Cronkite a straight deliverer of the news or did he use his platform to advance his opinion?

Almost certainly the former, because all of the incentives that he operated under favored being a straight deliverer of the news rather than being someone who shaded the news with his opinion. He was operating in a different market than someone like a Rachel Maddow or Sean Hannity. For his program to be successful, he needed to be believed by viewers all across the political spectrum. Maddow or Hannity don't. They just need the folks who share their viewpoint to believe them.

This doesn't hold up either. Witness Dateline NBC: https://www.latimes.com/archiv......
Doing sensational things for ratings has been a feature of media for decades.

Wait - 1993? Dope, you're showing your age. 1993 is well past the era that we're talking about. CNN launched in 1980, for Pete's sake - the media landscape had already been fracturing for a decade and a half by then. To the point where the fragmenting of media had already made its way into popular culture - Springsteen released 57 Channels (And Nothin' On) before that aired. I mean, Pat Buchanan had already parlayed his career as a very unabashedly slanted pundit into a serious Presidential campaign, nearly winning New Hampshire, a full year earlier.

That's exactly the point I'm making: One side of posters here can't claim victory by just dumping on something they don't like to read.

They're not "claiming victory." They're pointing out that when a proposition is asserted by a media outlet that is not engaged in actively assessing and interrogating claims before they publish them, they don't regard the proposition as having any support. If a reputable news organization reports something, people will assign that some weight and regard it as credible (though not necessarily proven) that the thing that was reported was true. If an outlet which exists primarily to provide content to an ideologically sorted audience reports something that is consistent with the predilections of their audience, it is fairly likely that they did not make any serious effort to interrogate the veracity of the proposition.