Who decides what is right and wrong? There are several common answers to this question including: the law, the government, individuals themselves. While these are the most common answers to the questions, they are deeply flawed and lead to very problematic outcomes when we begin thinking about actual real world ethical issues. Let’s look at each.
The Law: It is tempting to equate what is moral with what is legal. But, while there is a connection we need to be careful about thinking that the connection is one where the law defines what is moral. This would imply that in countries (like ours in the 19th century) where slavery was legal, that slavery was also moral. Rather, it is quite likely that morality is what informs what we decide is legal and illegal.
The government: This is even more problematic than asserting that the law defines morality. At least with the rule of law you can depend on there being a known standard for right and wrong. Even if the law doesn’t always codify our moral intuitions well, at least it is objective and (mostly) equally applied. But, even these safeguards evaporate in cases where the government defines morality. That means that what is moral is immoral rests solely on the whims of various, unaccountable individuals. This characterizes the worst examples of dictatorships and oppressive regimes. Is that what we want for a moral foundation?
The individual: This answer seems to be the most common but also contains serious problems. If each individual really gets to define for themselves what is moral and immoral then that pretty much means anything goes. There is no standard of conduct and no way for a society to function. As long as the rapist or child molester believes what they are doing is moral, then it is moral.
A better answer: There is a better alternative to these answers but it is not as intuitively obvious and is a more subtle concept. There is something fundamental in how our brains are wired up which is common to everyone that determines to some degree how we all think about right and wrong. Culture does have an effect on this which is why we see variation across cultures. But, if you look closer you see commonality as well at a deeper level.
This commonality can be seen across cultures in the same underlying moral rules each one has. As James Rachels points out in his book The Elements of Moral Philosophy, every culture has rules concerning truth telling, care of the young, and indiscriminate killing. While there is some cultural variation in these rules every culture recognizes the importance of telling the truth, caring for the young, and the need to prohibit indiscriminate killing.