I’ve been working on a project called When All Else Fails: Resistance to State Injustice. The thesis is of the book is simple: We have exactly the same rights of self-defense and defense of others against state injustice that we have against civilians. In the later chapters, I argue this holds true even if you are an agent of the government. (For instance, if a democratic president is about to commit an atrocity, his government-appointed bodyguards have the right to shoot him.)

However, one argument for the other side goes roughly as follows:

Government agents promise to follow orders. In virtue of making such promises and voluntarily accepting their roles, they become fiduciaries of the government. Thus, they have duties to perform unjust actions, or, at the very least, they may not sabotage or interfere with certain other government agents who commit injustice.

The problem with arguments like this is that they misunderstand how promises work. They also misunderstand what it means to become a fiduciary.

Suppose I say, “I, Jason Brennan, being of sound mind, promise to obey my frequent co-author Peter Jaworski in all things.” Suppose Peter and I sign a contract—I agree to follow his orders and in exchange, he pays me $10,000 a month. Now, such a contract might indeed obligate me to do some things. If Peter demands I refrain from watching House of Cards, the contract obligates me to follow. But suppose Peter says, “I demand you murder an innocent Syrian child, and, in addition, that you stop feeding your own children.” I have no duty to obey Peter here; on the contrary, my pre-existing duties to avoid killing innocent children and to feed my own children trump my promise.

Now one might believe that promises to governments are different. But unless we have a good argument to that effect, we don’t have any reason to believe it. If I promise to obey the president, and the president then tells me to murder a Syrian child, I don’t acquire a duty to kill the child, and the child’s rights do not disappear. That’s not how rights work. Rights are stringent side constraints held against other people. They do not disappear because you make a complicated promise to someone with a fancy title.

Before you make a promise, there are some actions you are forbidden to do, some you are obligated to do, and others that are morally optional. What promises can do is move some of the optional actions into the forbidden or obligatory categories. But they don’t move actions out of the forbidden or obligatory categories.

The fact that government agents have promised to obey the government does not excuse them when they obey unjust orders, nor does it relieve them of moral culpability for following those orders. This is a misunderstanding of how promises work.

Similar remarks apply to becoming someone’s fiduciary. Suppose I’m a lawyer. I have no obligation to defend a stranger. But when I become that person’s lawyer, I do acquire new obligations to help that person. However, I may not, e.g., threaten to murder the DA’s kids in order to get him to drop charges against my client. A parent cannot bash the knees of the kids on the rival basketball team to helps his kids win. A manager cannot dump toxins in the local park to maximize the profits of his shareholders. Fiduciary duties are like promises–you don’t lose your pre-existing duties in virtue of becoming a fiduciary.

Now, promises can change the moral status of optional actions. Acting in self-defense or in defense of others is often, if not always, optional. Thus, we might ask: can one lose the right to engage in optional self-defense or defense of others in virtue of making a promise to follow orders?

Frankly, that seems implausible. Suppose Batman and Superman are walking down the street. Superman says, “Batman, I’m thinking about retiring. But I know you’d prefer that I keep saving people. So, I propose an exchange. I’ll spend one more year doing heroic deeds, but only if you promise to do something for me right now. Don’t worry—I won’t ask you to do anything you are forbidden to do or required not to do.” Suppose Batman agrees. Then Superman says, “Ha! Gotcha! What I’m going to do right now is murder that kid over there. And, as you agree, according to the correct moral theory, saving that kid from me would have been supererogatory rather than obligatory for you. So, ha ha, now you have a duty not to stop me!” In this case, it doesn’t seem like Batman has acquired a duty not to interfere with Superman. Rather, it seems that Batman’s promise did not relieve him of the right to defend others. Or, if Superman had said he planned to kill Batman instead, it seems permissible for Batman to defend himself, despite his promise.