Being a network with a lot of, even exclusively, conservative opining is a perfectly valid choice for Fox to make. There is nothing wrong with opinion journalism that openly proclaims itself to be just that. But pretending to do straight reporting while choosing stories and dishonestly presenting nuggets of information in order to advance a political agenda perniciously undermines the work of the entire press and ill serves American democracy.
http://www.cjr.org/campaign_desk/the_real_problem_with_fox_news.php
