News reporting on television follows an official policy that says that a media outlet must present all sides of a controversial political issue.
In other words, journalism mustn't be biased and should be equal to all sides of an issue especially controversial political issues.
There exists a policy known as the fairness doctrine of the United States Federal Communications Commission (FCC), implemented in 1949, that required the holders of broadcast licenses both to display controversial issues of public importance as well as to do so in a honest, equitable, and balanced way.