The recent Supreme Court ruling in Berghuis v. Thompkins is another in the long line of opinions attempting to determine what the familiar words (to all you “Law and Order” fans), “You have the right to remain silent” really mean. At its core, however, it is about ethics.

The various opinions interpreting the landmark 1966 case ruling in Miranda v. Arizona, which ended the common police practice of sweating, beating and otherwise coercing confessions from criminal suspects in marathon interrogation sessions had, amazingly, never before dealt with the wrinkle presented in Thompkins. The suspect in a shooting was given the Miranda warning, but never said that he wanted his lawyer or that he refused to testify, as he had the right to do. He just sat through almost three hours of questions without saying a word, and then, near the end, uttered a one word answer, “Yes,” to the question of whether he would pray to God for forgiveness for the shooting.

This admission helped convict him at trial. The lawyers argued that the confession was illegally obtained, because the suspect’s three hours of silence should be read as his assertion of his Miranda rights. In one of those infamous 5-4 ideologically split decisions everyone complains about, the U.S. Supreme Court ruled against Thompkins. It’s reasoning: a suspect has to assert his rights to claim them. Until he says that he doesn’t want to talk and requests a lawyer, the police can keep asking him questions until he tells them to stop.

The opinion, like all opinions, is supported by citations to other cases in the Miranda canon, but these questions ultimately become ones of ethics as much as law. How best to balance the rights of the individual against the legitimate societal need for law enforcement? Liberals typically tilt to the side of the individual in these cases, an expression of principle over pragmatism, since they almost always involve the guilty. Conservatives are more likely to be willing to avoid absolute rights in the public interest, and give the police more leeway. Thomplins, as much as any Miranda case, was argued and decided on the issue of fairness. If the suspect truly understands his or her Miranda rights but doesn’t expressly assert them, is it fair and just for police to keep asking questions until he either answers or does assert those rights?

There’s a big “if” in that question, but assuming that “if” is met, I think the Supreme Court majority was right. If the suspect knows he can stop the questioning at any time, there seems nothing unfair about the police questioning him until he does. The interrogation is not coercion if the suspect has the power to end it, and knows that. The Court, it seems, could justify balancing the issue either way: requiring that the Miranda Rights be considered asserted unless the suspect expressly waived them, or holding that the Miranda warning simply informed the suspect of his options, and if he wants to avail himself of them, he needs to say so. The latter approach does not seem unfair, and it provides the police with the most flexibility. Heaven knows why Thompkins, after three hours of sitting silent, suddenly was moved to confess, but he clearly wasn’t forced to do it. He could have kept quiet, or ended the interview at any point.

I think the majority’s ruling was the most ethical option, balancing the competing interests.

You can read the opinion, and Justice Sotomayor’s dissent, here.