The economics of parking

Are there too few parking spaces in your city or campus … or too many? Professors Mikhail Chester, Arpad Horvath, and Samer Madanat try to calculate the social costs of parking in their six-page report “Parking Infrastructure and the Environment” published in 2011. (By the way, why can’t papers by legal scholars be this short?)

Where do I park?

Earth at night

What does this beautiful night map tell us about the relationship between population density and prosperity? Image courtesy of NASA Earth Observatory.


How many civilians, on average, do police forces in the United States kill each year? Legal scholar Richard Epstein, however, asks a different lethal-force question:

Police officer deaths in the line of duty, year to date for 2014, were 67 of which 27 were by gunfire. For the full year of 2013, the numbers were 105 total deaths, with 30 by gunfire. It would be odd to say that police officer deaths (which are more common than deaths to citizens from police officers) should not count…

In fact, according to the folks at DataLab at FiveThirtyEight, Richard Epstein has his facts wrong. The police kill on average 1000 people a year. (Hat tip to Alex Tabarrok.)

License to kill?


100-metre dash

Jamaica’s Usain Bolt is still the fastest man on the planet.

The legal philosophy of red-light cameras

Many cities around the world have installed high-tech red-light cameras at busy intersections to increase safety and raise traffic revenues — though some cities are already starting to phase-out these cameras. The debate over the legality of such cameras not only presupposes that many drivers run red lights; it also raises deep questions about the nature of law. The British legal philosopher H.L.A. Hart, for example, drew what many legal scholars now consider a crucial distinction between two types of legal observers or points of view: “external” observers and “internal” ones. So, what’s the difference, pray tell? According to Hart, external observers focus exclusively on the frequency of compliance or evasion with a given legal rule:

His view [i.e. the point of view of an "external" observer] will be like the view of one who, having observed the working of a traffic signal in a busy street for some time, limits himself to saying that when the light turns red there is a high probability that the traffic will stop.*

* See HLA Hart, The Concept of Law,” 3rd edition (2012), p. 90.

Internal observers, by contrast, contemplate the reasons or motives for acting in conformity with legal rules. For internal observers, “the red light is not merely a sign that others will stop: they look upon it as a signal for them to stop, and so a reason for stopping in conformity to rules which make stopping when the light is red a standard of behaviour and an obligation.” (Ibid., emphasis in original.) But is this a meaningful distinction in the real world?

Consider Hart’s simple traffic signal example again, not from the perspective of an observer, but from the perspective of actual drivers out on the road. (A better example would be posted speed limits, which hardly anyone complies with in real life, but let’s stick to Professor Hart’s own example for now.) The fact of the matter is that not every person will stop at a red light or a stop sign — have you done a “rolling stop” today? (Notice,by the way, that the rate of compliance is now easy to demonstrate empirically with traffic cameras.)

Many drivers will be tempted to run the light or stop sign and may, in fact, end up doing so, especially if there is no cross-traffic and if there are no visible police cars nearby. In other words, even so-called “internal” observers, who know the reasons for acting at a red light and know that they should stop, will adopt an “external” perspective in deciding whether to evade or comply with the traffic signal. That is, they will often choose to take a calculated gamble and evade compliance if such evasion suits their interests (e.g. saving time and avoiding the hassle of stopping). Furthermore, just because a driver stops at a red light or stop sign does not mean that he or she has adopted an internal perspective. Instead, she may have decided to stop at the intersection because she thinks that the probability of detection is high, not because she accepts the red light or stop sign as a legitimate or valid reason for stopping.

In short, Professor Hart’s philosophical digression in “The Concept of Law” about internal and external points of view is no doubt interesting but ultimately irrelevant, is it not? At the end of the day, we can measure rates of compliance (or evasion, as the case may be); we can’t measure, however, one’s internal reasons for one’s decision to comply with or evade a given legal rule. In fact, shouldn’t we be especially suspect of reasons for compliance or evasion, since such reasons are often ad hoc or are offered ex post to justify one’s behavior? (Traffic signal below courtesy of Gallery of Lights.)

Yellow = speed up?

Who won the Carr-Benkler wager?

The Carr-Benkler wager was a bet made way back in 2006 between Nicholas Carr, an internet critic and 2011 Pulitzer Prize finalist who coined the disparaging (but accurate) term “digital sharecropping” to describe Facebook’s exploitative business model, and Yochai Benkler, an internet champion and scholar who coined the more uplifting term “commons-based peer production” to describe the non-hierarchical model of online collaboration on such websites as Wikipedia. In brief, Professor Benkler bet that the most influential sites on the world wide web would be primarily “peer-production” systems (i.e. the content on such websites would be produced mostly by unpaid volunteers), while Carr bet that such sites would be mostly “price-incentivized” systems (i.e. the content would be produced mostly by paid employees or independent contractors). So, who won the bet?

Questions for Richard Epstein

On page 71 of his beautiful book The Classical Liberal Constitution, Richard A. Esptein acknowledges “how difficult it is to deal with systematic errors in [constitutional] interpretation that perforce creep into all interpretive efforts with the passage of time” (emphasis ours). Our question to Professor Epstein is this: What are the set of criteria for deciding which judicial precedents are in error and which are correct? How does one begin to test for “error” in an activity as subjective and aesthetic as constitutional interpretation? Is such a test even possible? Furthermore, how can our constitution be a “classical liberal constitution” if classical liberals don’t even exist anymore?

Where are all the classical liberals?