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If the Supreme Court is biased, which way does it lean?

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


There is nothing either good or bad, but thinking makes it so.

- William Shakespeare, Hamlet

According to a poll from the Pew Research Center that has come out just in time for this week's historic decisions on marriage equality, we should all be concerned. As it turns out, there's a tremendous amount of bias in our Supreme Court.


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Unfortunately, there's just one thing that people can't quite agree on: The direction in which this bias swings.

This disagreement, which I will get into shortly, harkens back to a study conducted all the way back in 1954. Two researchers were curious if people might actually construe the same objective stimulus differently based on their pre-existing beliefs and motivations, so they asked Princeton and Dartmouth students to watch the telecast of a football game that occurred between the two teams. Although they both saw the same exact game, you would never know it by reading how the different fans described the events that they had watched. Princeton students thought that the Dartmouth players made twice as many infractions as their own team did -- which also happened to be twice as many infractions as the Dartmouth fans themselves thought their own team had made. Essentially, they might have seen the same video, but they certainly did not see the same game. Each team's fans went into the viewing with their own set of biases and their own pair of eyes, and they ended up seeing what they wanted to see. Bias against your side might seem like something odd for someone to "want to see," but think about it -- even if you never necessarily want the media to be against you, it can sometimes be self-serving to believe (or maintain) that it is. After all, everyone loves an underdog. It's better to be the side that is unfairly persecuted and still manages to triumph than the side that gets the systemic privileges and benefits.This is why everyone hates referees; no matter how objective they are (or try to be), their calls are always going to seem like they're against you. This overperception of bias against our own side (and underperception of bias against our rivals) is referred to as selective perception, sometimes referred to specifically as the hostile media phenomenon if it refers to an oversensitive perception of bias in the media.

Two decades after the Princeton-Dartmouth study, a preliminary examination of registered voters leading up to the 1980 Carter-Reagan election began to lend some formalized support to this idea that we might see media forces as being particularly hostile towards our own side. Even though only 55 of the 160 voters that were polled reported thinking that there was an unfair bias in media coverage of the election, there was a clear pattern in the jilted voters' responses: Almost all of them thought that the media bias was running against their own side. Of the voters who planned on supporting Carter, 83% of them felt that the media was unfairly biased in favor of Reagan, whereas 96% of intended Reagan voters felt the opposite way about there being a slant towards Carter.

A second study conducted by this team of authors specifically tests how people with different ideological slants might respond to the same objective telecast of a controversial political issue. With this goal in mind, the research team showed media coverage of the 1982 Beirut Massacre to a wide variety of participants, some of whom were pro-Israeli, some of whom were pro-Arab, and some of whom were neutral or had no strong opinions (to serve as a control/comparison group). The researchers ultimately discovered that when pro-Israeli and pro-Arab participants viewed the exact same media coverage of the massacre, they once again appeared to have watched entirely different reports. Pro-Arab participants were significantly likely to think that the coverage was unfairly biased in favor of Israel, and they counted, on average, about 42 pro-Israel statements and 26 anti-Israel statements. Pro-Israel participants, on the other hand, only counted 16 pro-Israel statements -- 22% of the total number of statements that they noted down in their records. So, even after watching the same exact telecast, the pro-Arab participants still managed to count 26 more pro-Israel statements than the pro-Israel participants did.1

We can see the hostile media phenomenon at work in this most recent Pew Research Center's study, which asked Americans to report how they construe the current Supreme Court. As you can see in the table on the left (reproduced from the Pew Center's report), only 9% of conservative Republicans see the Supreme Court as being "conservative" like they are, whereas a full 48% of liberal Democrats think that SCOTUS has a clear right-leaning bias. On the other hand, 45% of the conservative Republicans are quick to call the Supreme Court "liberal," as opposed to the mere 15% of liberal Democrats who are willing to say the same.

Long story short, if you're a conservative, it's painfully apparent that the Supreme Court has a strong liberal bias. If you're a liberal, on the other hand, the Roberts court is obviously unfairly conservative.

No matter which way you lean, there's no denying it: The Supreme Court is clearly biased.

We're just not sure how.


1. Comparing these results with the neutral control group reveals that there were "objectively" (or as objectively as possible) about 19 pro-Israel statements, or 26%. This is not significantly different than the number of statements counted by the pro-Israel participants, so they were fairly accurate (the pro-Arab participants overperceived the frequency of pro-Israel comments). However, the pro-Israel participants were certainly not immune from the hostile media phenomenon just because their frequency counts did not happen to differ from the control group. Even though their counts did not differ on that one particular item, the pro-Israel groups were significantly more likely to think that Israel was treated more poorly overall in reports on the massacre, that unfair standards were being applied to Israel, and that the media was spending a disproportionate amount of time time focusing on Israel's role in the massacre.


Vallone, R., Ross, L., & Lepper, M. (1985). The hostile media phenomenon: Biased perception and perceptions of media bias in coverage of the Beirut massacre. Journal of Personality and Social Psychology, 49 (3), 577-585 DOI: 10.1037/0022-3514.49.3.577

Hastorf, A., & Cantril, H. (1954). They saw a game: A case study. The Journal of Abnormal and Social Psychology, 49 (1), 129-134 DOI: 10.1037/h0057880

Coe, K., Tewksbury, D., Bond, B., Drogos, K., Porter, R., Yahn, A., & Zhang, Y. (2008). Hostile News: Partisan Use and Perceptions of Cable News Programming. Journal of Communication, 58 (2), 201-219 DOI: 10.1111/j.1460-2466.2008.00381.x

Image of Shakespeare via Wikimedia Commons. Public domain image due to age; thought to be the work of a 17th-century painter named John Taylor.

Image of Sabra and Shantila (aka the site of the Beirut Massacre) courtesy of user deutsch_laender via Wikimedia Commons. Originally posted on Flickr. Available through a Creative Commons Attribution 2.0 Generic license.

Melanie Tannenbaum is a freelance writer and science communications consultant currently living in the Bay Area. She received her Ph.D. in social psychology from the University of Illinois at Urbana-Champaign in 2015, where her research focused on the science of persuasion and motivation regarding political, environmental, and health-related behavior. For more info, see her personal website.

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