Bias in peer reviewed material can be even more prevalent, especially for those that require publications for promotions or tenure.  People don't like to rock the boat and research tends to have a self-fulfilling aspect.  On top of that you have researchers that have a pre-determined belief in the outcome and instead of actual research simply manipulate the data until it presents the story they wish to tell.  I have seen first hand research which was stopped and not published because the result was contrary to the prevailing belief.  Not all is bad, but you would be ignorant to blindly believe that these experts do not sometimes push a predetermined belief.