Peering through that Window

Please forgive my lack of updating for the last two weeks, but between thanksgiving and drowning in assignments this blog had completely slipped my mind.
Anyroad...

I just finished interviewing my brother for an assignment in INF1300 (those in that class will know what I'm talking about). I found it to be an interesting experience. It was fun, but a little difficult. I found I kept trying to lead him into the answers I was looking for without even meaning too, because I wanted the data I was getting from him to fit the picture in my head of how I was going to construct my paper later on. Thankfully he is my brother and stated his opinion regardless of what I was trying (even unintentionally) to get him to say. However I began to think of how it might of gone if we hadn't been so familiar with each other. Would another person perhaps be more easily lead?
We briefly touched on in class (and with Knight) the issue of interviewees trying to anticipate what "right" answer the interviewer is looking for, thereby contaminating the data. At first I thought this to be a character weakness of the potential interviewee but now I think this has more with the interviewer and there unintentional fishing or leading. I'm also inclined to wonder how much might be portrayed not just by words but tone, facial expressions and body language, all those little ticks that happen that you don't contentiously notice but the other person might.
Since interviewing would be essential to my research topic, I wonder if it wouldn't be more prudent to get a third party to do the actual interviews rather than the person who has an emotional investment, so to speak, in the outcome of the data. Thereby reducing the possibility of data contamination?