I saw this. Stephi was actually better than you give him credit for - it's not just the words that matter, but the intonation. For example, "That's a pretty harsh charge" was more of a lead-in for Nickle's next statement to qualify, and was spoken more as a question. Also, what is biased about the two questions you cited?
Stephanopoulos: "Finally, Mr. McDermott, before you left for Baghdad, you said 'the President of the United States will lie to the American people in order to get us into this war.' Do you really believe that?"
Stephanopoulos: "But do you have any evidence the President has lied?"
Those seem pretty straitforward to me, and they definitely put the guys on the spot.
I agree. This is a pretty poor example of bias.