Involvement Type Matters: Examining Policy-Related News Exposure and Opinion Expression on Social Media

Informed by the social media political participation model, this study explored cognitive mechanisms by which social media exposure to policy-related news affects willingness to express opinions on the issue. A cross-sectional survey conducted in Hong Kong (N = 1,244) suggested distinct roles of two types of issue involvement in this process. A serial mediation model revealed the indirect influence of social media news exposure on opinion expression through outcome-relevant involvement, perceived behavioral constraint, and cognitive reactance in sequence, particularly among pro-democracy and centrist partisans. Value-relevant involvement, rather than outcome-relevant involvement, was found to mediate the association between social media news exposure and opinion expression. However, no variations in this relationship were observed across party orientations.