Since objective news coverage is vital to democracy, captured media can
seriously distort collective decisions. The current paper develops a voting
model where citizens are uncertain about the welfare e¤ects induced by
alternative policy options and derive information about those e¤ects from the
mass media. The media might however secretly collude with interest groups in
order to in uence the public opinion. In the case of voting over the level of
a productivity-enhancing public bad, it is shown that an increase in the
concentration of rm ownership makes the occurrence of media bias more likely.
Although media bias is not always welfare worsening, conditions for it to
raise welfare are restrictive.