Thursday, March 29, 2012

Fossil Law

The talk I described in my previous post dealt with a problem at the intersection of federal tax law and state marriage law. Thinking about it, it occurred to me that the problem was in part due to the existence of fossil law—legal rules that once made sense but no longer did.

Let me start with a science fictional example. At present, it is a safe assumption that most twelve year olds know less and are less mature than most adults. Given that, it makes sense to base legal rules such as who gets to vote or who is able to sign a binding contract on chronological age—despite the fact that some twelve year olds, such as one who was a baby sitter for our daughter when she was little, are more mature than some adults. The alternative would be considerably more complicated rules, requiring a larger element of discretion by whomever had the job of interpreting them.

Suppose the situation changes—genetic engineering, mind drugs, radically improved educational techniques, or the like, result in most twelve year olds being mentally and emotionally the equivalent of adults. The old laws might remain, for a while, despite the disappearance of the facts that had justified them.

For a real world example, consider the question of who counts as a child's parents. The old rule was that the mother was the woman from whose body the child was born, the father that woman's husband if she had been married and cohabiting with him at the time the child was conceived. The first part made obvious sense, the second served to eliminate legal controversies at a time when there was usually no better way of establishing paternity.

Neither rule makes sense any longer. The woman from whose body a child is born may be a host mother carrying another woman's egg. Paternity testing makes it possible to prove, beyond any reasonable doubt, that a particular man is or is not the child's father. The law has to some degree altered to take account of those changes, as in the California case of the child with five parents; the court ignored the literal implication of existing law and concluded that the couple with parental rights and responsibilities was the couple who had arranged for the child to come into existence, not the egg donor, sperm donor, or host mother. Adapting rules of child support to the existence of paternity testing has proved harder, probably because the relevant authorities are more concerned with finding some man to hold responsible for child support than with finding the right man.

Coming back to where I started, consider the same issue in the context of the tax treatment of married couples. Back when the federal income tax was created, and later when it was modified to permit joint returns, the typical married couple consisted of two people, one of whom was the principal money earner, the other responsible for running the household and bearing and rearing the couple's childen. Most married couples fit that pattern, and most couples that fit that pattern were married. The legal and social sanctions against unmarried sex, still more unmarried motherhood, were strong enough to discourage, for most couples, the option of separating the legal status of marriage from the reality of the relationship.

Even then, the map did not perfectly fit the territory. There were married couples where both parties were employed, there were households with the marital division of labor (minus the child bearing part) whose members were not married to each other—a parent and his or her adult child living together, two siblings, or some similar pairing. And there were some couples living in sin—married in fact but not in law, although if they were in a state that recognized common law marriage that might be only a temporary situation.  

But the standard model of marriage worked well enough so that it may have made sense to base tax rules concerning marriage on the assumption that all marriages fit that pattern, and everything that fit that pattern was a marriage. And unless the rules provided a really large penalty or bonus to being married, for most people that decision would be determined by other and more important considerations, so the IRS did not have to worry too much about tax rules driving people into or out of marriage.

None of that is true any longer. That suggests that, however the tax law chooses to deal with households in which individuals share, in some form, income and the work of household production, the defining rule should probably not hinge on whether the household members are legally married to each other. Which, among other things, would eliminate the problems associated with same sex couples that were the subject of my colleague's talk.

For a very different example of the  problem, consider the crime of statutory rape, sex with an underage partner. In legal theory, criminal liability requires intent. In practice, statutory rape is a strict liability crime. Even if the offender did not know the age of his partner, even if the partner fraudulently misrepresented her age, perhaps with the assistance of a borrowed driver's license, the adult partner is potentially liable for a serious felony. That, at least, is my understanding of the law—readers who are better informed are welcome to correct it.

Sixty years ago, before the pill and the sexual revolution that it helped to produce, that did not represent a serious problem from the standpoint of the legal authorities. It was true that it meant that someone engaged in non-marital sex with a relative stranger was at risk of committing a serious crime without knowledge or intent. But non-marital sex, especially with relative strangers, was not something that the relevant authorities had any objection to discouraging.

For an example of that attitude a little earlier, consider the explanation of the "usefulness" requirement in patent law offered by a prominent 19th century jurist. He explained that there was no reason not to grant a patent on something of no use to anyone, since nobody would have any reason to infringe it. What the requirement was intended to prevent was the patenting of inventions that were positively pernicious—such as a device to facilitate private assassination—Judge Story apparently anticipated James Bond, the CIA, and targeted drone strikes—or debauchery. 

Modern patent law imposes a more stringent interpretation of the usefulness requirement, but it would be hard to argue that devices to facilitate debauchery—viagra, say, or the pill itself, or online software for locating sex partners—are pernicious, hence unpatentable. While modern norms do not regard casual sex as the ideal, they do take it largely for granted.

In a society where meeting a stranger in a singles bar and ending up in bed with her is not merely legal behavior but acceptable behavior, there are serious problems with a legal rule that can lead from a one night stand to several years in prison without requiring either knowledge or intent. Whether those problems will eventually lead to changes in the law I do not know. But they probably should.

Readers are welcome to offer other examples of fossil laws, and suggestions of how they might best be changed.

Wednesday, March 28, 2012

The Supply Function for Marriage: A Natural Experiment

Today I attended an interesting talk by a colleague, on the tax consequences of the clash between state and federal law. Her particular interest was a current problem—same sex couples who were recognized as married, or the equivalent for purposes of taxation, by the state they lived in, but not by the IRS. Her description of the historical background to the problem, the past interaction between state law and federal taxation, suggested to me an interesting but unrelated idea—the possibility of using a past legal anomaly as a natural experiment to determine the supply elasticity of marriage.

Federal tax law, now and in the past, bases its definition of what income belongs to which taxpayer on state law. In a community property state, back before the invention of the joint return, half of a couple's income was attributed to the husband, half to the wife. In states that did not recognize community property, on the other hand, the husband was taxed on his income, the wife on hers. 

When tax rates become significantly graduated in response to the need to pay for WWI, that meant that  high income single-earner couples paid substantially lower taxes in community property states. One possible response was for such couples to move to community property states, and apparently some did. Another would be for a high income bachelor living in a community property state to get married, thus shifting half his income to his wife's lower rate. 

Which get us to my natural experiment. The situation I have described lasted for twenty years or so, easily long enough for individuals to observe it and respond. Was one response an increase in the fraction of high income men living in community property states who were married, relative to the fraction in non-community property states? If so, the size of the effect would give us a measure of the elasticity of supply of marriage—how the number of people who get married responds to financial incentives to do so.

It should be a good project for a PhD thesis, assuming the necessary data—marriage rates by income group and by state—exist.

Tuesday, March 27, 2012

Alcohol, Warming, and Professionally Correct Speech

Recently, while driving, I listened to a satellite radio program called "Doctor Radio," talk radio by doctors.

In the course of the program, the question of alcohol and health came up. All of the participants agreed that evidence showed that a moderate level of alcohol consumption, something like one beer a day for a woman, one or two for a man, or the equivalent in other drinks, was good for you, better than no alcohol at all. All of them also agreed that they would not advise their patients to act on that evidence.

They did not offer an adequate explanation  for the apparent inconsistency. There was mention of the fact that a higher level of consumption was dangerous, in particular likely to lead to auto accidents, and that there were problems with prescribing something that depended on the exact dosage—but distinguishing one beer a day from three is not  a difficult problem, even for those who are not doctors. 

My conjecture was that the real explanation was the reluctance of doctors to appear to be on the wrong side. Everyone knew that alcohol was a bad thing, a source of auto accidents and various medical (and other) problems. By giving a truthful account of the medical evidence, the doctors on the program might appear to be pro-alcohol, when all good people were  anti. Hence they had to qualify their conclusion as a purely theoretical matter, not something that would actually affect what they told their patients. Think of it as a different version of PC—Professionally Correct speech.

It reminded me of a similar pattern in a different context. From time to time, I see a news story on some piece of scientific research that somewhat weakens the case for taking strong action against global warming—for instance, work suggesting that, while the IPCC projections were correct about the expected magnitude of warming, they overstated its uncertainty, and hence the risk of some outcome much above the center of the reported distribution of results.

I believe that every time I have seen such a report, it was accompanied by a quote from the researchers to the effect that global warming was a serious problem and their work should not be taken as a reason to be less worried about it. They almost certainly believed the first half of that. On the other hand, their work was a reason to be less worried, if not a reason to stop worrying. 

Good people are on the side that believes that warming is happening, is anthropogenic, and is a serious problem that needs to be dealt with immediately. Bad people deny one or more of those claims. If that is what all the people who matter to you, in particular the fellow members of your profession, believe, and you are so unfortunate as to produce results that strengthen the bad people's case, it is prudent to make it clear that you are still on the side of the angels. Just as, if you are so unfortunate as to be an honest doctor aware of the evidence in favor of alcohol, it is prudent to make it clear that have not transferred your allegiance to demon rum.

Tuesday, March 20, 2012

Is Meat Bad for You?

I came across a convincing critique of the recent headlines claiming that eating meat greatly increases your chance of dying. The discussion is fairly detailed; the critic pretty clearly doesn't believe that the conclusions reported can be consistent with the data, given what appear to be internal inconsistencies: A larger effect after controlling for other factors then before, despite the fact that the other factors are mostly getting worse as the amount of meat eaten increases. 

But the real killer fact is much simpler. The studies reported on covered two groups of people over a period of more than twenty years. Total mortality from all causes was less than one percent. So what is being reported as a 13% increase in mortality due to eating one more serving of meat is, assuming everything in the study is correct, a 13% increase in a mortality rate of less than one percent, or an additional mortality of about one in a thousand over twenty plus years. 

I also found another piece offering a more general criticism of results of this sort—claims about the effect of nutrition based on studies of what some large group of people ate and what happened to them. Such results are often newsworthy but, at least according to the author of that piece, always or almost always fail to be supported by followup studies.


Looking at the reports more carefully, I think the critique is wrong in at least one important respect. The death rate is not less than 1% for the whole study period, it is less than 1% per year. The total death rate over the period appears to be about 20%, which greatly weakens the force of the argument I cited.

Sunday, March 18, 2012

Nordhaus on Global Warming

A correspondent points me at the work of Nordhaus and Boyer, attempting to estimate the externality from CO2 production and the appropriate response. I have not read the printed version, but there is a webbed version available. A number of things strike me:

1. Their conclusion is that 
"current approaches, such as the Kyoto Protocol, are highly inefficient, with abatement costs approximately ten times their benefits in reduced damages."
2. In order to get even that result, they depend on including costs from a very uncertain estimate of the risk that global warming will result in low probability catastrophes of one sort or another: 
"this approach is taken because of the finding of the first-generation studies that the impacts on market sectors are likely to be relatively limited."
Or in other words, without including the costs from such catastrophic risks, global warming doesn't seem to be a serious problem.

3. They estimated the cost from low probability catastrophes by asking a lot of experts how likely they thought it was that there would be a catastrophe, assuming a given rise in global temperature, that would reduce world GNP by at least 25%.

Even if one takes seriously the output of that sort of procedure, there is a striking asymmetry in their approach. They do not appear to have asked any experts what the chance is that preventing global warming would cause a catastrophe—or, to put it differently, that global warming will prevent one. Yet, as I keep pointing out, earth's climate was not designed for us, hence there is no a priori reason to assume that large negative results due to a few degrees of warming are more likely than large positive ones.

This is a striking illustration of my general critique of the "add up the externalities" approach to policy issues. Possible changes can have both positive and negative effects. If you want to conclude that something should be prevented, you focus on the negative effects, ignore or minimize the positive ones, and claim to have an objective argument to support your conclusion. That is precisely what Nordhaus and Boyer have done. The only surprising part is that, even after doing that, they still got only a weak version of the (presumably) desired conclusion.

This leaves me wondering what the pro-global warming view of Nordhaus and Boyer is. Their conclusion  weakens the case for something like the Kyoto protocol--and that conclusion hinges on a procedure that cannot, I think, be defended. Correct that error and their work appears to provide no support for any substantial effort to prevent global warming.

P.S. After writing this, it occurred to me that there is one respect in which I am being too hard on Nordhaus and Boyer. Suppose we limit "catastrophes" to changes that are not only unlikely and very large, but also very fast. Then there really is some asymmetry to the situation. Humans are currently optimized against the current environment, making any change presumptively negative. I have argued in the past that that is not a strong argument with regard to changes that occur slowly—for example three degrees of warming in a century—since humans will in any case be changing what they do in many ways over so long a period. But that argument would not apply to a change that occurred over only a few years.

If, for instance, climate change makes Europe unbearably cold but adds an equal amount of acceptable land elsewhere, say in northern Canada, and does it in only a couple of years, there will be a very large net cost.

So they would have a legitimate case if they limited their category of catastrophes to rapid ones—but, so far as I can tell from what they wrote, they did not.

Monday, March 12, 2012

Iceland, Shari'a, and the Reliability of Oral Transmission

I have recently been reading up on the history of Islamic law, in particular in Knut Vikør's excellent Between God and the Sultan, for my current book project on legal systems very different from ours. While doing so, it occurred to me that there is at least one issue common to scholarly debates on that subject and debates on the legal system of saga period Iceland, the subject of a different chapter of my book. That issue is the reliability of oral transmission of a prose text.

In the Icelandic case, the question is part of a very old scholarly debate on the origin of the sagas. The family sagas describe events of the tenth and early eleventh centuries. Their texts, however, were written in the thirteenth and early fourteenth centuries. Were they composed at the time, using bits and pieces of the earlier history, in which case their description of the earlier society may largely reflect later conditions, or were they composed shortly after the events they describe, transmitted orally, and finally committed to writing?

The strongest evidence against the latter theory is that, while the sagas sometimes have skaldic verse embedded in them, they are themselves prose documents. Reliable oral transmission over a period of centuries is more plausible for verse, a point actually mentioned by Snorri Sturluson in his introduction to Heimskringla, his saga history of the Norwegian kings. 

Jesse Byock, a leading modern scholar, has offered some ingenious evidence on the other side. The hero of Egilsaga (one of my favorite sagas), his father and his grandfather exhibit a set of traits that fit the symptoms of a hereditary disease, Padget's syndrome, not known until the 19th century. It seems implausible that all of those apparently unrelated details of the story would have stayed together for the three hundred years between the events and the writing down of the saga, unless they had been combined into a single narrative composed shortly after Egil's death and transmitted thereafter as oral literature.

What about Islamic law? It purports to be based on two sources, both reflecting divine revelation—the Koran and the Hadith. The latter are traditions of what Mohammed and his companions did and said. The theory is that, since Mohammed was divinely inspired, his practice provides evidence of how God wishes believers to act—including men making and enforcing legal rules. 

Since the traditions can be used as evidence for and against various interpretations of the law, there was an obvious incentive to fabricate suitable ones, a point recognized by Islamic legal scholars. There was thus an extensive scholarly project in the early centuries to separate out the reliable traditions from the unreliable ones, based in part on each tradition's isnad, the account of who heard it, whom he told it to, and the series of oral links through which it was transmitted until it was eventually written down.

Some recent scholars, primarily western, have challenged this traditional account, arguing that all or almost all of the traditions are bogus, invented long after Mohammed's death in the course of disputes over alternative versions of the law, versions themselves based largely on non-religious sources—pre-Islamic Arab law, the legal traditions of the conquered provinces, and the administrative rules created by the conquerors in the early years. Their arguments depend in part on analysis of the supposed chains of transmission, in part on evidence that many of the supposedly genuine hadith deal with issues that could not have arisen in the early period from which they claim to date. Curious readers can find an entertaining discussion of one small part of the controversy in "The Truth About Cats and Dogs," an essay by Vikør.

By now the relation between the two controversies should be clear. Our understanding of the legal system of saga period Iceland depends, in part, on how willing we are to believe in the oral transmission of prose texts, the original versions of the sagas, over a period of centuries. Our understanding of the history of Islamic law depends, in part, on how willing we are to believe in the oral transmission of prose texts, the traditions of what Mohammed and his companions said and did, over a period of centuries. In each case, the alternative interpretation of the evidence, implying an alternative view of the history of the relevant legal system, is that the texts were actually invented by the people who wrote them down.

Sunday, March 04, 2012

Chavez, Assad, and the American Left

My guess is that Americans who consider themselves left wing tend to approve of Hugo Chavez, as they have, traditionally, tended to approve of Fidel Castro. I would also guess that, like most other people, they tend to disapprove of Bashar Al-Assad and his violent suppression of opposition in Syria.

Chavez, however, is one of the few national leaders to support Assad. Assuming my guesses are correct, how do American (or, for that matter, European) leftists deal with the situation? One might view it, on a much smaller scale, as analogous to the problems faced by communists and those sympathetic to communism at the time of the Hitler/Stalin pact.

Friday, March 02, 2012

Colliding Seminars

This semester I am teaching two seminars, one on Legal Issues of the 21st Century and one on Legal Systems Very Different From Ours. Two days ago they collided.

The topic for the day in the legal issues seminar was human reproductive technology; one of the issues that came up was gender ambiguity. It is convenient to think of all human beings as either male or female, and it is a pretty good approximation, but no more than pretty good, for reasons some of which have only been discovered recently. Some humans are neither XX nor XY and so, genetically speaking, neither male nor female. Some humans are genotypically male but phenotypically female, or vice versa, presumably due to something going wrong in utero. Some humans are, judging by their own accounts, genetically and morphologically of one gender but psychologically of the other—and modern medicine makes it possible for them to surgically correct the error, although imperfectly. Finally, it has been known since antiquity that some humans are hermaphrodites (the politically correct term seems now to be "intersex," although it  covers a wider range of conditions), possessing both male and female sexual organs. 

All of which raise potentially interesting problems for legal rules, norms, cultural patterns that are based on the simple binary categories—a subject covered in an interesting paper by one of my students a few years back. So far as I know—readers are welcome to correct me if I am mistaken—these issues were ignored in traditional Anglo-American law. 

They were and are, however, treated in some detail in traditional Jewish law—one of the systems covered in my other seminar. That legal system recognized two categories other than male and female. One consisted of hermaphrodites. The other was labelled "tumtum" and seems to have been a condition in which the genitals were somehow concealed—at least, the discussions assumed the possibility that surgery might reveal whether a tumtum was actually male or female.

Under Jewish law, the religious obligations of men and women are different. That raised an obvious question—what were the obligations of someone in one of the other categories? One answer given by some sages was that, since such a person might be either male or female, he/she/it was obliged to do anything required by religious law of either a male or a female—just to play safe. Others apparently felt that ambiguous cases should be considered male. Doing a little last minute research to see how the ancient law dealt with the modern problem, I came across a web page discussing various opinions, ancient and modern, on the application of Jewish law to individuals of ambiguous gender—pretty obviously written by and for people to whom it was still a live issue in a living legal system.

Thursday, March 01, 2012

A Better Way of Learning

One problem with the usual approach to education at all levels is that it mostly consists of having someone learn something not because he at the moment has any need to know it but because someone else told him to learn it, possibly on the grounds that the knowledge or skill will be useful at some time in the future. It is much easier to get someone to actually learn something if it is of immediate use to him. The best way of learning a computer language, in my view, is not to start by working your way through the manual but to start with a program you want to write. You then have an immediate incentive to learn what you need to write it, and immediate feedback as to whether you have succeeded.

That approach works in a wide variety of other contexts. When my home schooled son was about eleven or twelve, he was running a weekly D&D game for a group of other home schooled kids. It was good training in responsibility. Each week, when the other players showed up, he had to have already done all of the work of preparing that week's session—otherwise the game, his project, would fail. Each week he did. It was, I think, better training than if he had been a student with homework due on a regular schedule. The homework would have been someone else's requirement, with no justification other than someone else's orders. This was his project—and it was obvious what he had to do to make it work.

Suppose you are a comfortably well off parent. Almost everything your child wants—toys, books, games—is available to be bought at what is, in terms of your income, a trivial cost. That makes it hard to do a believable job of teaching your child the importance of saving, of deciding which things he really wants and which he can do without, skills that he will need, as an adult, to function in a world of limited resources.

If your child plays World of Warcraft, he will learn the relevant lesson with no need for you to impose arbitrary limits. He will have a limited amount of gold and a considerable variety of things he would like to spend it on. Increasing that amount will require him to spend time doing daily quests,  figuring out what he can craft and sell at a profit and crafting and selling it, or perhaps, if he is a mage, running a magical taxi service teleporting other characters hither and yon for pay. Whatever his effort, he will probably not end up with enough gold to buy everything he wants. Here again, the lesson works because it is, in its own odd way, real. These are the things he has to do in order to achieve the objectives he has himself chosen.

I was reminded of the same point today in a very different context. At lunch there was a talk on the Northern California Innocence Project, which is run out of, and largely staffed by, the law school I teach at. The purpose of the project is to identify people who have been convicted of crimes they did not commit and get their verdicts reversed and them released. While the project involves some lawyers and at least one faculty member, a lot of the work is done by law school students. Seen from one side, the purpose is to get innocents out of prison. Seen from the other, it is to help educate our students. 

Considered as education, it is a strikingly successful example of the  approach I have been discussing. The students are learning legal skills, how to interview witnesses, convince judges, prosecutors, juries, file the right paperwork, make the right legal arguments. They are learning those skills not because someone else has told them they will need them five years from now to do the work someone then will pay them to do, but because they need the skills now to do something they very  much want to do, to right a wrong, to rescue someone unjustly imprisoned. 

Pretty clearly, it works.