While it's certainly true that everything we think and believe is a summation of everything we've learned and that has gone on in our lives since we were born, it is still possible to look at things objectively. The problem is: people who do NOT look at things objectively will say you aren't doing it, either, since you do not agree with them.
If you are looking at things objectively, you cannot use logic which says that, regardless of what the facts say, there could be some information not yet made public which will support a different conclusion. It may be true, but it's really just an excuse for refusing to accept or even look at the facts.
If you are looking at things objectively, you cannot assume that everyone who disagrees with you is lying.
If you are looking at things objectively, you cannot simply look for alternative explanations for everything that does not fit your beliefs.
I had no particular interest in who sent the anthrax when I began doing my research. I was just tired of listening to nothing but opinions and speculation which seemed to totally ignore the facts. So, being an analyst, I thought it might be interesting to look at the facts to see what the facts had to say. And, that's what I did.
But, people who disagree with me can claim that I just twisted things to fit my beliefs, and I cannot prove them wrong. So, I'm immune to opinions and speculation and only change my analysis when confronted with FACTS.
Yes, facts can be twisted to fit any theory. That's why we have courts of law. And that's why we have "scientific method". And that's why I have to rely on MY analysis until proven wrong by solid facts.