I believe the correct answer is: Deontological ethical theory.
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   In moral philosophy, deontology (or deontological ethnical theory) is an ethical theory which judges the morality of an action based on whether that action itself is right or wrong under a set of rules. One of the examples is that killing is wrong even if it’s self-defense.
   Given that he consistently tells the truth, is fair with my employee, feels a strong moral obligation to make decisions that do not infringe on the rights of my staff, he is applying the concepts of deontological ethical theory.