THE PERSUASIVE POWER OF GREEN: A 2x2 Experimental Study on Colour and Persuasion Knowledge in Environmental Policy Communication

Abstract

This study investigates the persuasion effect of colour, specifically green, on environmental policy advocacy in political communication. Although business research has shown that colour can influence consumer behaviour and attitudes, there is a lack of systematic research on whether it has a similar effect in political communication. To fill this research gap, the researcher uses the Persuasion Knowledge Model (PKM) and colour congruence as a theoretical basis to examine whether green can enhance people's attitudes and support towards environmental policies. This experiment adopted a 2 (background colour: green vs. grey) × 2 (persuasion knowledge level: high vs. low) design and collected responses globally through an online survey. The result showed that although green is considered to have a higher congruence with environmental messages, it does not significantly increase people's advertisement attitude and policy support. Persuasion knowledge has a stable effect on attitude, while there is no significant interaction between it and the background colour. The findings suggest that it is challenging to drive changes in attitudes and behaviours and use green in the political field, despite its symbolic connotations with the environment. The result also challenges the colour persuasion theory in political communication.