Most believe that the DNC favored Hillary Clinton for their party's presidential nomination. Bill and Hillary Clinton are a powerful political family within the Democratic Party. Therefore, it is no surprise that the DNC has such a close relationship to Hillary's campaign. Her campaign got to dictate the terms for her party's primary debates. Also, there was a close working relationship between many in the Clinton campaign with those working at the DNC.
Throughout the entire primary election the DNC has been favoring Hillary Clinton as their top pick candidate. The Democratic party has decided that Hillary is the next Democratic nominee long before the primary elections. According to the recent DNC leaks they have been running consistent pro-Hillary campaign. Now the DNC is filled with Hillary's campaign staffers.
I believe the DNC and the media as a whole favored Hillary Clinton, and chose to put their support behind her far too soon in the election process. When compared to Bernie Sanders, Hillary Clinton dominated the news cycle on a daily basis. I don't believe the DNC or media acted fairly.
Of course they did because she is the obvious choice to become President. Bernie sure in the hell wasn't going to take the Presidency so why shouldn't they back her. It just makes good political sense. That is the how the world of politics works, both of them know that.