The effect of traffic light veracity labels on perceptions of political advertising source and message credibility on social media

The use of warning labels on political advertisements is one way to help citizens better evaluate the source and veracity of messaging, and combat the harms of misinformation on social media. Reliance on labeling is part of a larger policy push for greater transparency on social media platforms with respect to the source and quality of information. In this study, we test the effectiveness of “traffic light” labels (red, orange, green) as indicia of the veracity of political advertisements on YouTube. In an online experiment (N=1,054), we test seven variations of TL-veracity labels and find that red and orange traffic light labels placed concurrently with the start of a political advertisement significantly affect credibility perceptions. Taken together, the findings suggest that direct-to-consumer labels can be effective inputs to credibility perceptions, but their effectiveness depends on timing and position.