Undergraduate Honors Theses

Thesis Defended

Spring 2019

Document Type


Type of Thesis

Departmental Honors



First Advisor

Leaf Van Boven

Second Advisor

Tiffany Ito

Third Advisor

Lewis O. Harvey Jr.

Fourth Advisor

Jennifer Wolak


Previous research has demonstrated a “party over policy” effect, in which politicians will support a piece of legislation from their own party regardless of the policy content, even if that content runs contrary to their ideological or explicit goals. This study evaluates a similar effect: the perceived believability. In this study 179 undergraduates at the University of Colorado at Boulder were asked to rate how believable statements were from members of different political parties, varying the specificity of the content of the statement. Participants rated statements from their political outgroup as being less believable than statements from their political ingroup, particularly when the content of the statement is ambiguous, and therefore open to interpretation guided by group membership cues.

Available for download on Saturday, April 10, 2021