Freedom can be seen as the underlying assumption of all the various schools of ethical thought, both secular and religious. Freedom is what we need to have—or, at the very least, must suppose we have—if we’re to make meaningful moral decisions. If we have no freedom, if we’re little more than automata, then it becomes impossible to judge people’s actions in any meaningful sense.

No matter how reprehensible we may find someone’s actions, we cannot reasonably subject them to moral censure if they had no freedom in what they were doing. If we see people as being nothing more than the product of their genetic inheritance or their immediate environment, then we are no longer in a position to exercise any judgment on people’s behavior.

A moment’s reflection should alert us to the potentially catastrophic consequences of the abandonment of freedom in the realm of ethical thought. If we are deemed not to have the freedom to make choices in our lives, then how can society possibly hold anyone accountable for their actions? What becomes of the criminal justice system when individuals who commit crimes are deemed not to be in possession of free will? How can we possibly punish someone for a crime if they effectively had no choice in the matter?

Even at the most superficial level, then, freedom is essential to ethics. Those who advocate determinism, who argue that there is no such thing as free will, still support the idea of having a criminal justice system that punishes those who transgress society’s norms, laws, and standards. The difference, however, is that they put aside their philosophical beliefs and proceed on the basis that freedom is a legal fiction necessary to maintain stability and order in society. In other words, for the good of society, determinists are prepared to treat criminals as if they had freedom, even if they believe they don’t really have such freedom.

The idea of freedom is fundamental to the idea of ethics, but it is also controversial. Ethically, individuals have to be conscious and free to make their own decisions. If they are not free in their decision-making, then the ethical value of their decision is tainted. Imagine the infamous trolley problem, where you have control over a switch that changes the tracks a trolley is traveling upon. On one track lies an incapacitated man; on another track, which the trolley is currently on, lie five individuals. You have the choice to switch between the tracks, choosing to kill one person with action or five people with inaction.

At the root of this question is an issue: there is little freedom. The freedom to choose what to do is compromised because you will have to kill one set of individuals, regardless of your choice. Can it be considered unethical in that situation to willingly kill one person if your only other choice was to kill five? In terms of absolute truth, you have still caused the death of one person, but in terms of relativism, you have saved a difference of four lives. The freedom to choose the best outcome is a fundamental tenet of ethics, and when it is limited, the value of our ethical decisions is hindered proportionally.

Ethics are based on an individual having the freedom to make a choice between one act or another act. Without that freedom, there can be no ethical decision making. Therefore, freedom is integral to behaving ethically. If you have no choice, you have been robbed of your humanity and are merely functioning as a tool.

For example, if somebody stronger than you clamps your hand over a gun and forces your finger to pull a trigger and kill another person, you cannot be held ethically responsible for the act: you had no choice. The person who held your hand and pushed your finger is the responsible party.

Trouble comes, in certain cases, in defining whether a person had a choice (was free) when they performed an unethical act. For example, people who killed Jews in Nazi Germany argued that they had no choice and were only following orders. This argument was rejected, but people will often contend that if the only choice is death or complying with an act that violates your ethics, that is not really a free choice. Is it permissible to kill a person because somebody else has a gun aimed at your head and is telling you to do so or die? The choice doesn't seem particularly "free" at that point, but ethical purists—for example, Kant—might argue that you do have a choice: dying yourself, or killing the other person. Therefore, since you could choose, you are ethically responsible for the killing. Others would take a more moderate approach, but the point is that these are difficult decisions. What is clear, however, is that ethics involves choices, and without freedom, choices can't be made.

From a religious point of view, freedom is important in ethics for two main reasons.

First, when we speak of freedom, we are saying that people are capable of making decision without coercion. They are able to choose to do good and are able to choose to do evil. This is fundamental to any discussion in ethics. For example, if a person is forced to do something "immoral" or "wrong," then the ethics is compromised. To put a gun to someones head or a loved one's head makes decision harder to make.

Second, freedom also assumes that there is intentionality. In other words, people intentionally make an active decision to commit or not to commit to something when there is freedom. In the end, a person is making a decision based on their own freewill. This makes a person responsible for his or her actions.