Discuss the role of the criminal investigator. (in 150 words)

Criminal investigators have to conduct investigations about a crime or felony. They have to process crime scenes by doing crime recognizion, scene documentation and evidence gathering. They have to operate inside the law. They also have to begin a preliminary survey. They have to give hypothesis or possible theories about what happened so at the end they have to eliminate the theories that don't have evidence to be proved and reinforce the one that can conduct to the solution of the case. In doing all of these, they need to evaluate all the evidence in an impartial way, which is in fact, from my particular point of view, the most difficult thing since we are human beings and we are subject of thousands of  prejudices or ideas that mislead us from taking correct decisions. Let's say what happens if one person in a crime investigation is seen a really bad person and is also addicted to many drugs, then investigators have the impression that this person is guilty of a particular crime since nobody likes that person and even biased investigators want that person to be guilty. However, good investigators have to be cold and not let whatever thing happen to contaminate the evidence with prejudices.    

answer; overt behavior;

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