Everyone knows the Miranda warnings. We have heard them ten thousand times on TV.

Not everyone knows their significance—clients often ask me whether it’s significant that they were not read their rights when they were arrested. It is not; the rule of Miranda is this: A statement made by a defendant as a result of custodial interrogation is not admissible against him unless, before making the statement, he was advised of certain of his Constitutional rights. So the police only need to read you your rights when they are going to question you while you are in custody. Under Texas law the mere reading of rights has no legal significance—the reading must be documented by audio recording or acknowledged in writing by the defendant—so Texas cops don’t bother to read arrestees their rights.

In New York v. Quarles the Supreme Court created a “narrow” exception to the Miranda rule. The reasoning was that public safety trumped Miranda’s stated goal of ensuring that subjects of police interrogation knew their rights:

The doctrinal underpinnings of Miranda do not require that it be applied in all its rigor to a situation in which police officers ask questions reasonably prompted by a concern for the public safety.

In a sense, any questions calling for incriminatory answers might be seen as “reasonably prompted by a concern for the public safety.” But that’s not the sense in which the Court decided Quarles:

The police in this case, in the very act of apprehending a suspect, were confronted with the immediate necessity of ascertaining the whereabouts of a gun which they had every reason to believe the suspect had just removed from his empty holster and discarded in the supermarket. So long as the gun was concealed somewhere in the supermarket, with its actual whereabouts unknown, it obviously posed more than one danger to the public safety: an accomplice might make use of it, a customer or employee might later come upon it.

(Mr. Quarles was not thought to have an accomplice, so this is really about guns being so terrifying that the possibility of a law-abiding citizen finding one creates a sufficient danger to public safety to change the rules. Scratch that: it’s really about nibbling away at the Constitution.)

For a situation to justify unwarned interrogation, the information sought is—by definition—important independent of its admissibility. If something is going to be trumped by public safety, it should not be the procedures the police must follow if they want the information they obtain to be admissible. It should instead be the police desire that all information be admissible.

Even before Quarles, if the police wanted information that they thought they wouldn’t get from an arrestee who knew his rights, they could seek that information without advising the arrestee of his rights. Before there was a Quarles public-safety exception to Miranda, society was no worse off for the police decision to conduct an unwarned interrogation seeking inadmissible information rather than giving the warnings in hopes of garnering admissible information.

The press has talked about the government “invoking the public-safety exception,” but the exception is not some magic spell that gives the FBI forty-eight hours to talk to a heavily drugged arrestee without Mirandizing him and then use the information obtained at trial. Quarles clearly does not cover information gleaned with questions other than those “reasonably prompted by a concern for the public safety,” and while the government may want to broaden it, they cannot without the cooperation of the courts. When the Boston Police Commissioner says, “We’ve told the people of Boston we feel that they’re safe at this point in time,” that’s a good indicator that further interrogation is not prompted by the “immediate necessity” that existed in Quarles.

But where the Supreme Court makes an exception, the Supreme Court always broadens the exception. Quarles is the top of the slippery slope…the jackbooted foot in the door…the flesh-eating camel’s nose in the tent.

Others have pointed out that the police do not need to get admissible evidence through interrogation if they have enough against him already. Maybe what Tsarnaev tells the FBI won’t matter to the trial of his case. Maybe the government will have a cut-and-dried case against without using the product of his interrogation. Maybe the admissibility of the product of his interrogation will never be litigated. But “maybe” implies “maybe not,” and here I suspect not.

I expect that the admissibility of Tsarnaev unwarned statements to the government will be litigated, and I expect that the outcome of that litigation will not be convivial to our freedom. The spirit of the times, carefully cultivated by the government and the media, is one of fear, and the courts will move in rhythm with that spirit, making it easier for the government to put terrorists in boxes.

But when the government talks about “terrorists,” they’re talking about the people who they can claim are terrorists. And when they are talking about the people who they can claim are terrorists, they are talking about you and me. 

Five years from now we’ll be talking about U.S. v. Tsarnaev as another step closer to tyranny.

(See also Gideon and Greenfield on Quarles, Burney on Miranda, and Greenfield again on two-step interrogations.)