do democrats realize if you have a personal or professional bias against someone you cannot be part of a team that investigates them ?

This is not quite true.  It can give the appearance of unfairness whether or not there is unfairness.  This is an question of ethics, and I don't think any republican or republican supporter can make any valid argument that questions the ethics of anyone.

It is definitely possible for an honest and ethical person to investigate, and even judge, another despite any personal feelings.  You cannot project your own ethical failings onto another and expect them to be as weak as you.  Not everyone uses power to abuse enemies.  There are actually people who find such thinking to be abhorrent and incompatible with roles of responsibility in investigation and judgement.

If the person is one likely to apply personal bias in the performance of their duties, they should not be in a job or position where they perform duties that bias can affect.  It ought to follow directly that anyone in such a role should be presumed to be fair despite any personal feelings they might possess.  They should have been fired from that job long ago if this is not true.  And if they never have shown such unacceptable behavior in the past, then you are complaining about something without any basis in reality.

Who, specifically, are you complaining about here?  Let's get right to the point.  You clearly have someone in mind that you feel is prejudiced about a target of investigation to the extent that the person should not be trusted to be fair in the exercise of their duties. You make a scurrilous claim, and I would like to see if it is warranted.

one the secretary of state and the president is responsible for all consulate buildings and staff, they were responsible to make sure they were secured and did not even try to get them help, obama hid under his bed, Clinton did nothing

Remind me again of how many years it was that Republicans spent trying to pin the tragedy at Benghazi on Hillary?

@Allen ... If Hillary was even technically guilty, all those years of all those separate Republican instigated investigations would have turned up something to show her guilt. But, they didn't do that. And, it was a Republican controlled Congress that refused to give the State Department the funds requested to bolster security.

Democrats think their witch hunts are okay. They take cues from the socialist governments of USSR, Cuba, etc 

Someone should have told that to Kenneth Starr.

Someone should have told that to the EIGHT (8) separate republican controlled Congressional committees who each SEPARATELY investigated Hillary Clinton and Benghazi.

Sorry, you can't change policies made by repubs due to inconvenience.

Having watched Republicans do just that everyone is aware. 🙄

but that takes away half the fun ...