There is a lot of good social cost stuff here. I hope to revisit it later. But for now, it suffices to say that Posner’s opinion in ACLU v. Alvarez focuses more on the costs to collective safety by privileging this liberty interest, rather than the costs to liberty by protecting collective safety:

A person who is talking with a police officer on duty may be a suspect whom the officer wants to question; he may be a bystander whom the police are shooing away from the scene of a crime or an accident; he may be an injured person seeking help; he may be a crime victim seeking police intervention; he may be asking for directions; he may be arguing with a police officer over a parking ticket; he may be reporting a traffic accident. In many of these encounters the person conversing with the police officer may be very averse to the conversation’s being broadcast on the evening news or blogged throughout the world….

Privacy is a social value. And so, of course, is public safety. The constitutional right that the majority creates is likely to impair the ability of police both to extract information relevant to police duties and to communicate effectively with persons whom they speak with in the line of duty. An officer may freeze if he sees a journalist recording a conversation between the officer and a crime suspect, crime victim, or dissatisfied member of the public. He may be concerned when any stranger moves into earshot, or when he sees a recording device (even a cell phone, for modern cell phones are digital audio recorders) in the stranger’s hand. To distract police during tense encounters with citizens endangers public safety and undermines effective law enforcement.

The majority opinion disclaims any intention of “immuniz[ing] behavior that obstructs or interferes with effective law enforcement.” I am not reassured. A fine line separates “mere” recording of a police-citizen encounter (whether friendly or hostile) from obstructing police operations by distracting the officers and upsetting the citizens they are speaking with. Today’s ruling may cause state and federal judicial dockets in Illinois to swell because it will unwittingly encourage police officers to shoo away bystanders, on the authority of cases like Colten v. Kentucky, 407 U.S. 104, 109-10 (1972); cf. City of Houston v. Hill, 482 U.S. 451, 462 n. 11 (1987); King v. Ambs, 519 F.3d 607, 613-15 (6th Cir. 2008), when the officer wants to have a private conversation in a public place.

Police may have no right to privacy in carrying out official duties in public. But the civilians they interact with do. The majority opinion “acknowledge[s] the difference in accuracy and immediacy that an audio recording provides as compared to notes or even silent videos or transcripts” but says that “in terms of the privacy interests at stake, the difference is not sufficient to justify criminalizing this particular method of preserving and publishing the public communications of these public officials” (emphasis in original). The assertion lacks a supporting argument, and by describing the recording as a “method of preserving and publishing the public communications of these public officials” neglects the fact that the recording will publish and preserve what the civilians with whom the police are conversing say, not just what the police say.

The further statement that these “are not conversations that carry privacy expectations even though uttered in public places” implies that anything said outdoors is ipso facto public. Yet people often say things in public that they don’t expect others around them to be listening to, let alone recording for later broadcasting, and we are given no reason to think that this is never the case when someone complains to a police officer, or otherwise speaks with one, “in public” in the sense of being in a place in which there are other people about.

Suppose a police detective meets an informant in a park and they sit down on a park bench to talk. A crime reporter sidles up, sits down next to them, takes out his iPhone, and turns on the recorder. The detective and the informant move to the next park bench to continue their conversation in private. The reporter follows them. Is this what the Constitution privileges?

It is small consolation to be told by the majority that “the ACLU plans to record openly, thus giving the police and others notice that they are being recorded” (emphasis in original). All the ACLU means is that it won’t try to hide its recorder from the conversants whom it wants to record, though since the typical recorder nowadays is a cell phone it will be hidden in plain view. A person who doesn’t want his conservation to be recorded will have to keep a sharp eye out for anyone nearby holding a cell phone, which in many urban settings is almost everyone. The ubiquity of recording devices will increase security concerns by distracting the police.

There is more on the state’s side of this case than privacy of communications and the effectiveness of law enforcement — and the more is the same First Amendment interest that the ACLU says it wants to promote. The majority opinion concedes that “conversational privacy” “serves First Amendment interests,” but thinks there can be no conversational privacy when the conversation takes place in a public place; it says that “this case has nothing to do with private conversations.” But private talk in public places is common, indeed ubiquitous, because most people spend a lot of their time in public places; because they rely on their anonymity and on the limited memory of others to minimize the risk of publication; because public places are (paradoxically) often more private than private places (imagine if detectives could meet with their informants only in police stations); and because eavesdropping on strangers is actually rather uncommon because it is so difficult in most cases to understand a conversation between strangers…

I disagree with the majority that “anyone who wishes to speak to police officers in confidence can do so,” and “police discussions about matters of national and local security do not take place in public where bystanders are within earshot.” Forget national security; the people who most need police assistance and who most want their conversations kept private are often the people least able to delay their conversation until they reach a private place. If a person has been shot or raped or mugged or badly injured in a car accident or has witnessed any of these things happening to someone else, and seeks out a police officer for aid, what sense would it make to tell him he’s welcome to trot off to the nearest police station for a cozy private conversation, but that otherwise the First Amendment gives passersby the right to memorialize and publish (on Facebook, on Twitter, on YouTube, on a blog) his agonized plea for help? And as in our informant example, many of the persons whom police want to talk to do not want to be seen visiting police stations.

Accuracy is a social value, and a recording of a conversation provides a more accurate record of the conversation than the recollection of the conversants: more accurate, and also more truthful, since a party to a conversation, including a police officer, may lie about what he heard or said. But on the other side of the balance are the inhibiting effect of nonconsensual recording of conversations on the number and candor of conversations (and hence on values that the First Amendment protects); the baleful effect on privacy; the negative effect on law enforcement; and the litigation likely to be engendered by police officers’ shooing away intruders on their private conversations with citizens. These are significant social costs, and the majority opinion offers no basis in fact or history, in theory or practice, in constitutional text or judicial precedent, for weighting them less heavily than the social value of recorded eavesdropping.

H/T Eugene Volokh