Tige Richardson’s recent piece on the media’s dismissive attitude toward Bernie Sanders’ campaign is the latest evidence against the myth that there is a liberal or left-wing bias in the mainstream media. And while its transparent, unanimous, and extremely premature declaration of Hillary Clinton’s nomination as “inevitable” seems to suggest otherwise, this de facto endorsement of her candidacy reveals the true nature of the mainstream media’s bias – one that is centrist, corporate, and establishment.

One of the best diagnoses of this bias was articulated by press critic Peter Hart of the media watchdog group, FAIR. When Washington Post columnist Dana Milbank compared Jim DeMint to Elizabeth Warren in 2014, Hart rightfully pointed out that the two have essentially nothing in common – given the former’s denial of climate change and opposition to gay and lesbian teachers compared to the latter’s advocacy for regulating Wall Street and protecting consumers.

“[T]o argue that Warren is the left equivalent of DeMint, one must exhibit no interest in the substance of politics,” Hart wrote.

Hart made the same point in response to Milbank cautioning the Democrats against encouraging its populist supporters on purely comparative, substanceless grounds – warning that it could cost Democrats seats in the same way that the tea party’s insurgency had at times cost Republicans seats. Again, Hart took issue with his relativistic comparison, as well as with Milbank's appraisal of the virtues of frictionless and moderate politics:

“It’s a little strange to suggest that a political movement on one side of the spectrum is equivalent to a movement on the opposite side of the spectrum – unless your point is that centrism knows best,” Hart said.

“Centrism knows best” is a cogent distillation of what always has – and still does – pass for conventional wisdom.

The portrayal of Bernie Sanders as the left-wing nuisance to the pre-ordained nominee is the latest example of this centrist bias, but it is certainly nothing new.

In 1984, for instance, Jesse Jackson was accused of “weakening the image” of Walter Mondale, the Democratic Party's eventual nominee. After Mondale's victory, the media applauded the Democrats on their move to the center: “Democrats’ Platform Shows a Shift From Liberal Positions of 1976 and 1980,” ran the headline of one New York Times analysis that year.

approvingly declared that, “he Democratic Party of 1988 is more unified, more single-minded, more obsessed with winning and less with ideology.”

Despite that apparent migration, the conventional wisdom still held – four years later – that the party needed again to move to the center. In 1988, after the nominee Dukakis had spurned Jesse Jackson at the party's convention, The Chicago Tribune

You get the picture, but it goes on.

for leaving behind the supposed liberalism of Mondale and Dukakis (who, we were told, had already done just that). Then, two years later, mainstream pundit Cokie Roberts advised Clinton to “ove to the right” – the

In 1992, President Clinton was applaudedsame advice that the Democrats received following the 2014 midterms.

It is from this vantage point that the oft decried bias against conservatives can be put into proper perspective: the centrist media disapproves of conservatives insofar as they are “extremists” and approves of them insofar as they are “moderates" (again placing politicians on an absurdly reductive "political spectrum").

Conservative media critics have already noticed

biased coverage in favor of “top-tier” candidates such as Jeb Bush and Marco Rubio, and against more “fringe” candidates such as Rand Paul and Ted Cruz.

This centrist bias applies to issues as well as candidates. Take, for instance, the last few budget debates in Washington: the media was far more eager, as Paul Krugman observed, to hold up Paul Ryan (R-Wis.) and his budgets as models of moderation and non-ideological wonkishness than it was to present an alternative case – the People’s Budget as proposed by the Congressional Progressive Caucus – which it effectively ignored because of its emanation from the “far-left.”

While this bias could be attributed to a noble yet impractical attempt at “balance” and “fairness,” there is also an economic component to the media’s centrist and pro-moderate bias.

It ought not be a secret by now that a majority of the nation’s media outlets are owned by only a handful of corporations. And while the corporate media is rightfully flogged for a number of practices – sensationalism, "infotainment," superficial reporting, the blending of news and opinion, and self-promotion – its pro-corporate bias is seldom criticized.

The corporate media has been especially coy, for instance, in its coverage of the Trans-Pacific Partnership – a massive free trade deal written by and for corporate interests. While the heads of the largest media companies are personally and institutionally concerned about the terms of the deal – especially over intellectual property and “fair use” rules – the major news networks hardly feel it is worth informing the public about.

A Media Matters study of nightly newscasts found that CBS, ABC, and NBC made no mention of the TPP between August 2013 and January 2015.

If the TPP is mentioned, it is usually to track the deal's forward momentum following bipartisan agreement by the parties' moderate factions rather than to allow for a critical debate of the deal's merits.

When journalist Lee Fang asked Joe Scarborough, the host of MSNBC's Morning Joe, about the lack of coverage of the TPP, Scarborough replied, "Richard Haass brought this up. He came on set. President of the CFR [Council on Foreign Relations]. He said he wanted to talk about this and I poked him and said, ‘C’mon, let’s talk about the new Star Wars trailer.’"

Morning Joe, while it appears on the liberal MSNBC, nevertheless epitomizes the third component of the media's bias, which is essentially pro-establishment. Priding itself on its popularity among "influencers," Morning Joe is a kind of televised kaffeeklatsch where politicians, advisers, experts, and reporters engage in playful political banter.

Its more-than-cozy relationship with those in power was displayed when President Obama's adviser, Valerie Jarrett, entered the set and exchanged -- in candid footage -- warm embraces with journalists Katty Kay and Cokie Roberts. At the end of the video, Scarborough, the ex-Republican representative, can be heard saying, "Valerie, come give me a hug.”

This episode is symptomatic of the nonpartisan, cliquish, and clubby culture that sustains the Beltway's insular worldview. Here is Mark Leibovich's depiction of a Mardi Gras-themed party held in 2010 for Betsy Fischer, then the executive producer of NBC's Meet the Press:

McAuliffe, the former Democratic National Committee chairman, arrived after the former Republican National Committee chairman Ed Gillespie left. Fox News’s Greta Van Susteren had David Axelrod pinned into a corner near a tower of cupcakes. In the basement, a very white, bipartisan Soul Train was getting down to hip-hop. David Gregory, the “Meet the Press” host, and Newsweek’s Jon Meacham gave speeches about Fischer. Over by the jambalaya, Alan Greenspan picked up some Mardi Gras beads and placed them around the neck of his wife, NBC’s Andrea Mitchell, who bristled and quickly removed them. Allen was there too, of course, but he vanished after a while — sending an e-mail message later, thanking me for coming.

In this case, Allen refers to Mike Allen, the chief political reporter for Politico, whose "Playbook" newsletter recounts the social activities of the Washington elite. A recent dispatch, for instance, recounted that top reporters, pundits, and national security officials recently rubbed shoulders during a cocktail party while chatting over veal and octopus salad.

It's no wonder, then, that most mainstream news shows and talk shows are as bland as they are – given the generally fraternal atmosphere among Beltway figures. It's hard to believe that this coziness does not affect the media's reporting.

Meet the Press's current host, Chuck Todd, for example, admitted that he allows his guests to drone on and evade his questions out of politeness. When asked why he isn't more aggressive, Todd said, "We all sit there because we all know the first time we bark is the last time we do the show... All of a sudden, no one will come on your show."

But there is another reason that the media is so protective of the establishment, and it has again to do with economic interests.

In addition to corporations subsidizing the media through commercials, the major networks also rake in lots of money during election cycles – especially from corporate and tycoon-funded political advertisements.

In 2012, the president of CBS, Les Moonves, said, “Super PACs may be bad for America, but they’re very good for CBS.”

Moonves anticipates that the company will financially see “strong growth with the help of political spending" as the 2016 election cycle begins. In an investor call, he added, "thank God, the rancor has already begun.”

But how does this information support the claim that corporate media organizations are biased in favor of the establishment?

Based on a study by Adam Bonica and Jenny Shen, the wealthiest donors tend to support more moderate candidates. They note that establishment politicians like Orrin Hatch (R-Utah) and Ben Nelson (D-Neb.) raise 10 times more from elite donors (those in the top 0.01 percent) than from small donors, whereas more "fringe" politicians like former Texas Representative Ron Paul and Alan Grayson (D-Fla.) raise 10 times more from small donors.

While perhaps counterintuitive, recent evidence bears this out. Rand Paul and Bernie Sanders – whose campaigns are generally taken less seriously by the media – are largely reliant on small donations. The biggest donors, on the other hand, are supporting more establishment figures whose campaigns are deemed to be more viable.

Mega-donor Sheldon Adelson, for instance, said Ted Cruz is "too-right wing" and is looking to back a more "established" candidate.

A chart diagramming this relationship between corporations, the media, and politicians would look a great deal like the "iron triangle" that characterizes how special interest groups sway legislators and capture regulators: In this case, corporations not only own much of the press, but the major networks also rely on advertisements to subsidize their operations.

The media then generally puts a positive spin on issues and candidates that favor corporate interests, including more moderate and establishment politicians who, like the press, depend on big money to support their campaigns.

The evidence for this centrist, corporate, and establishment bias is most plain when contrasting its treatment of "insiders" and "outsiders," such as the campaigns of Clinton and Sanders.

Sanders is routinely asked, for instance, if his real intention is not to win but merely to "pull Hillary Clinton to the left," implying that his greater distance from the mythical center makes him unelectable (despite the popularity of many of his ideas).

Likewise, given his seemingly "anti-corporate" policy positions (such as breaking up the largest banks and blocking the TPP) and his rejection of contributions from elite donors, reporters question whether he has the resources necessary to run a "credible" campaign.

Finally, given his political independence and long history of anti-establishment politics, the Beltway press dismisses him as a pesky outsider with no real chance of overtaking Clinton (who, despite her fraught relationship with the press, nevertheless has many supporters and sympathizers among the mainstream commentariat).

But it's not only political outsiders that suffer from this kind of media bias. By being so insular, by narrowing the range of acceptable ideas and political discourse, and by deeming some candidates more viable than others (especially before a single debate or primary), the media is doing all Americans a disservice.

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