Public service broadcasters and commercial media outlets with media bias in the changing media environment

In the current media environment, some commercial media outlets are offering more biased news than ever before with some public service broadcasters (PSBs) even appearing to disseminate biased news under political pressure. Under such conditions, can the media system ensure political accountability? This study theoretically examines how increased commercial media bias and politically pressured PSB bias affect political accountability and social welfare and discusses the role of PSBs in the changing media environment. We construct a two-period retrospective voting model in which voters obtain information from biased news. First, we present the conditions under which political accountability works even when biases exist. Second, we examine a case in which a PSB is politically pressured and present the bias selected by the PSB and the level of political accountability. We find that even if commercial media bias becomes extremely high, there are still cases in which political accountability works. Third, regarding two situations in which a PSB is mandated not to broadcast biased news and is politically pressured, we demonstrate how social welfare changes with an increase in commercial media bias and explore the social significance of PSBs. We discover that in the case of the anti-incumbent commercial media, when commercial media bias becomes relatively high, the existence of PSBs can always improve social welfare, even if PSBs are politically pressured.