In 4.5 minutes, on the Bill O'Reilly Show, Sharyl Attkisson of cBS (note the small "c") tells why she left that network.

It is a 4.5 minute clip.  You have the time.  Just keep in mind,  that Attkisson is a proud Democrat and an Obama supporter,  or, at least she was all of this,  at one time.  Her existence,  also,  works against the conservative narrative,  often heard,  that a liberal journalist cannot be objective.  "They" can,  but most believe that the "times are so critical,  that objectivity does not serve the greater good"  (this is the message coming out of MSNBC,  in 2009).  

Attkisson details how she was limited in her reporting on three of the larger scandals of this Administration,  an "Administration of Lies" (my wording).