Lazy, not biased: Susceptibility to partisan fake news is better explained by lack of reasoning than by motivated reasoning

Authors: Gordon Pennycook, David G Rand
Publication: Cognition, July 2019

TL;DR

Two studies with 3,446 participants found that people who score higher on cognitive reflection tests (measuring analytic thinking) are significantly less likely to believe partisan fake news—contradicting the "motivated reasoning" theory that political bias drives misinformation susceptibility. The effect holds regardless of political ideology, suggesting lazy reasoning rather than partisan motivated reasoning explains fake news belief.

Key claims

• Main finding: Analytic thinking predicts reduced susceptibility to fake news across ideologies, not increased polarization (as motivated reasoning theory would predict).
• Cognitive Reflection Test: Participants who do better on reasoning problems are better at discerning fake from real news.
• Not partisan filtering: More analytical people are not more credulous of fake news matching their political ideology; they reject all implausible headlines more effectively.
• General skepticism: The effect is strongest for obviously implausible headlines; more analytical people have better intrinsic BS detection, not just ideological skepticism.
• Replication: Results held across two independent studies with different item sets and sample sizes.

Methods

The studies used versions of the Cognitive Reflection Test (CRT)—problems requiring deliberative reasoning—to measure analytic thinking. Participants rated the accuracy of: - Fake news headlines (both Democrat-consistent and Republican-consistent) - Real news headlines (both consistent and inconsistent with their ideology)

The researchers then examined the correlation between CRT score and perceived accuracy, testing two competing theories: 1. Motivated System 2 Reasoning (MS2R): Deliberation exacerbates partisan bias, so high-CRT individuals are more credulous of ideologically favorable fake news. 2. Classical reasoning: Analytic thinking supports sound judgment regardless of ideology, so high-CRT individuals reject implausible fake news across all partisan conditions.

Results consistently supported the classical reasoning account.

Significance

This work challenges the popular narrative that partisanship is the primary driver of fake news belief. It suggests interventions should target reasoning engagement (getting people to actually think critically) rather than trying to overcome partisan motivation, which may be intractable. The findings align with prior research showing analytic thinking supports skepticism toward conspiracy theories, religious claims, and other epistemically suspect beliefs.

Connections

• Related to A Survey of Fake News: Fundamental Theories, Detection Methods, and Opportunities on cognitive and psychological mechanisms of fake news belief.
• Complements Social Media and Fake News in the 2016 Election on fake news in 2016 election; Allcott & Gentzkow documented the prevalence and scope of fake news exposure while Pennycook & Rand elucidate individual-level susceptibility mechanisms.
• Contrasts with motivated reasoning theory applied to political belief (Kahan et al.); this paper argues that for fake news specifically, system 1 laziness rather than system 2 motivated reasoning is the primary driver.
• Part of growing literature on Cognitive reasoning and Fake news detection focused on analytical thinking as a protective factor.

Notes

Pennycook and Rand's framing as "lazy, not biased" has become influential in the misinformation literature. The emphasis on cognitive effort (system 2 engagement) opens avenues for interventions: making people pause, reflect, and apply existing knowledge. However, the paper focuses on headline-level judgments; real-world sharing behavior and longer-form disinformation may involve different mechanisms. The CRT is a narrow measure of analytic thinking, so generalization to other forms of reasoning should be tested.