Ethics are not relative to the situation; they are based on long-standing norms of society. Ethics/ethical behavior is based on certain immutable traits of character (i.e. virtues) such as honesty, integrity, trustworthiness, respect, responsibility.

The ends do not justify the means. The way in which you get to your goal is just as important as getting there. If not, you might rationalize an unethical action by saying it accomplishes your goal.