No, it is not possible to entirely leave out bias in research, current events, or the judicial system. The reason is bias is a type of personal preference and comes from an individual's perspective and experiences. It is natural to conclude that bad experiences will have an impact on a person's view of the world. But the facts are facts and in any case cannot be changed. In such cases, bias would not contribute to the conclusion because the facts themselves do not change. Factual conclusions give no leeway to either opinion or bias, For example, adding 2 and 2 give the factual conclusion of 4. However, the opinions and bias can come in how the person would view the number 4.

Humans aren't the only ones to create an opinion, animals express an opinion too. They just express it in different ways. Usually, it is based on an unfavorable action. Expressing an opinion does not mean you are biased. It can indicate bias but it does not mean that this is actually the case. The opinion could also be made on the facts and not the perceptions. While perceptions hold sway, they only contribute a part to an overall opinion. But how much perception contributes is dependent on the individual, their mood, and their response to their emotions. The key question is can the person separate their emotional responses from the facts?

There is nothing wrong with having an opinion. While bias and opinion are related in the sense they can affect each other, they should not be considered to be completely interlocked together. The simple reason is that opinions can change more easily than bias by the sheer presentation of new facts, while bias is more personal in nature and requires more concrete positive influences in order for it to change.

There is a fundamental problem with the way you apply the word opinion to the word bias in your question.

By definition opinion is "belief based not on certainty but on what seems true or probable."
Bias is partiality (favoring something over another) or prejudice (an opinion held in disregard of facts that contradict it). Source - Webster's New World Dictionary and Thesaurus.

Bias - holding an opinion in disregard of contradictory facts is extremely different from opinion which is based on known information.

In the USA, our judicial system is entirely based on opinion - opinion being the result of deduction based on self-evident truths (in other words - facts). Whereas, thankfully, it is not based on bias - holding to a predisposed preference in spite of fact. The same principle applies to research.

Essentially the premise of your question is faulty as opinion and bias are not really interchangeable. So, based on that, to specifically answer your questions:

Everyone having an opinion is not a function of promoting or eliminating bias.
Yes, it is possible to leave out bias in research, current events and the judicial system.
(Bias can exist in research, current events and the judicial system, but it can also not exist.)
Expressing an opinion does not mean you are biased (although certainly you can be).
Nothing is wrong with having an opinion. In fact, it is often essential to your survival.
And finally, no, the two words bias and opinion should not be interlocked (or interchanged).

Its called morals, principles, and honor .
People do know what these things are still dont they ?

Now, I suppose I have some principles. Let's see...., I never double dip, I only use the f*ck when the children present are over the age of 12, and I've haven't killed anyone (yet)

And, I suppose I have some morals. Let's see, I dont lie or steal from customers or the elderly and dont cheat on tests.

And, I suppose I have some honor. but then again everyone has an opinion on that one.....

~X