Slate media bias rating is Left.

In September 2018, AllSides conducted an editorial review of Slate. We decided to move Slate from a Lean Left media bias rating to a Left media bias rating. 

The AllSides team found that Slate never includes a Right-leaning perspective on its website, making it unbalanced. Opinion pieces on Slate are clearly labeled news, making it unclear to readers what is fact and what is opinion. In its news reporting, Slate often uses subjective and emotional words.

At the time of review on Sept. 6, 2018, we noted that multiple pieces of Slate content labeled "news" were not balanced, and gave readers only a Left perspective on issues of the day. For example, that day a piece on the site claimed that the Brett Kavanaugh Supreme Court nomination is "a matter of life and death" for women — a subjective statement. Another piece claimed the Trump administration was "ignoring" rules against indefinite detention of undocumented children, when in reality the administration released documents proposing to amend them. Another Slate piece labeled "news" opened, "Donald Trump, who is somehow the president, did an interview..." AllSides determined Slate's framing of these issues and subjective language has a clear Left media bias.

According to the 2014 Pew Research study, a clear majority of Slate's audience (76%) is left-of-center.

As of August 2018, before AllSides shifted its Slate media bias rating, 1,436 AllSides readers agreed that Slate's media bias rating is Lean Left. On average, those who disagreed rated Slate as Left.

In December 2016, Fox News published a piece titled: "BIAS ALERT: Slate switches from defense of Electoral College to calling it a tool of white supremacy."

About Slate

 According to WikipediaSlate is an "online magazine that covers current affairs, politics, and culture in the United States from a liberal perspective."

Slate is a United States-based, English language online current affairs and culture magazine created in 1996 by former New Republic editor Michael Kinsley, initially under the ownership of Microsoft as part of MSN. On 21 December 2004 it was purchased by the Washington Post Company. Since 4 June 2008 Slate has been managed by The Slate Group, an online publishing entity created by the Washington Post Company to develop and manage web-only magazines. Source: Wikipedia

The AllSides Media Bias Rating reflects the average judgment of the American people.

The AllSides Media Bias RatingTM reflects the average judgment of the American people. We don't use a convoluted mathematical or artificial intelligence model, but instead have regular people representing the broad spectrum of Americans blindly rate the bias of articles. That produces a fair, verifiable bias rating.

This media bias rating was determined using the following levels of bias verification.

Basis of Rating:

Blind Survey
Third Party Data
Community Feedback
Editorial Review
Secondary Research

Confidence Level:

Low or Initial Rating

Unless otherwise noted, this bias rating refers only to news articles on their web site, not from opinion pieces or what is broadcasted on TV or radio. The opinion writers from the same media source may have different bias ratings, so individual writers often are rated separately.