3. THE VALUE OF WOMEN UNDER POLYGYNY AND BRIDE PRICE

Polygyny is a particular form of polygamy involving men marrying multiple wives. Becker first analyzes this topic in Becker (Reference Becker1974) in a section pertinently entitled “polygamy” and then in the chapter on polygamy in Becker (Reference Becker1981). He examines many determinants of the likelihood that societies have polygamy and that individual men and women live in polygynous households. He also analyzes consequences of polygyny. Becker (Reference Becker1974, pp. S19–20) claims that allowing polygyny is good for women: “Surely, laws against polygyny reduce the “demand” for women, and thereby reduce their share of total household output and increase the share of men” and “the laws that prevent men from taking more than one wife no more benefit women than the laws in South Africa that restrict the ratio of black to white workers benefit blacks”.

In the Treatise Becker (Reference Becker1981, p. 56) drops these strong statements, but in response to “groups opposing polygyny (who) claim to be opposed to the degradation and exploitation of women” he continues to state that polygyny is good for women. His conclusion is based on a D&S analysis of marriage, an analysis similar to that of the effect of a higher sex ratio: under a polygynist regime it is as if there were more men in the market than under monogamy. However, as Grossbard (Reference Grossbard, DaVanzo and Simon1980) and Becker (Reference Becker1981) point out, allowing the same men to enter a market, for wives, twice does not have the same effect as the presence of twice as many men. Even if all men are identical and women are plotted on the horizontal axis, under polygyny men's demand becomes a step function to the extent that wives have diminishing marginal productivity when one factor in marital production is fixed: the husband's time. The gain from marriage, and what men are willing to pay for a wife, will then be a decreasing function of the number of wives already in the household. Nevertheless, as shown in Becker (Reference Becker1981, Figure 3.2) the demand for wives is higher under polygyny than under monogamy, and for a given supply of women their market price and access to marital income will increase.Footnote ¹¹

Becker's argument can be explained with the help of Figure 1 depicting juxtaposed markets for wives in two otherwise identical societies, except that one allows polygyny and the other does not. The quantity dimension is number of wives. The implicit price of wives is f, women's share of marital full income (including home production). To make the analogy with other D&S analyses, more apparent I drop the assumption of identical men and identical women and assume instead that there are many types of men and many types of women. In assuming this, I follow Becker's (1973) hedonic D&S model and traditional labor economics (see previous section).

D ₁ is men's demand under polygyny: like employers who can hire more than one worker men can marry more than one woman. Individual men enter the market whenever a wife's value to them exceeds her market price f and market demand is the sum of all individual men's derived demands at given prices for wives. The first men to enter are those with whom women generate the most marital surplus and those with higher marginal utility from marital output. The demand for wives is downward-sloping for at least two reasons: (1) as men with lower productivity and utility from marital output enter the market they are willing to pay less to marry; and (2) for a given man the gain from marriage to a particular wife is a decreasing function of the number of wives already in the household due to diminishing marginal productivity of wives.

Men's market demand for wives under monogamy, D ₂, lies under D ₁, reflecting the fact that men's individual demands for wives are capped to one wife only. The upper portion of demand D ₂ corresponds to individual demands for first wives and coincides with that portion of D ₁. However, as the number of wives on the horizontal axis increases, under monogamy men demand fewer wives: quantity demanded grows as price f decreases due to the entry of less productive men, not due to re-entry of polygynists.

The market supply is the sum of all individual supplies by women derived at given implicit prices f. Whenever that price exceeds their reservation income women enter the market. The market supply is upward-sloping as the women with the lowest reservation incomes enter first. Women's supply in a polygynist regime could lie above that under monogamy to the extent that women prefer not to share a husband and ask for a higher price from polygynists than from men offering monogamous marriage. However, for simplicity it is assumed that the supply is the same in both societies.

The market with polygyny clears at equilibrium e; the market imposing monogamy at equilibrium e′. Under polygyny the demand is relatively higher and there is more male competition for relative scarce women who obtain a higher equilibrium income f_p than they would under monogamy (f_p > f_m). This higher implicit price translates into more access to consumption goods for married women. Therefore, according to Becker and my doctoral dissertation written under Becker's supervision (Grossbard Reference Grossbard1978a) women are better off under polygyny than under monogamy. Becker (Reference Becker1981, p. 56; italics added) warns us, however, that marriage markets may not necessarily be competitive: “My analysis of efficient, competitive marriage markets indicates . . . that the income of women . . . would be greater when polygyny is greater if the incidence of polygyny had been determined mainly by the relative marginal contribution of women to output.”

The price that women obtain in a polygynous marriage market may not fully capture their contribution to marital income based on their productivity and may be lower than f_p. For example, there may be a ceiling on the price of wives, which can be analyzed in light of Becker's (1981, pp. 86–87) D&S analysis of price ceilings in marriage markets (where the term “price ceiling” is not explicitly used). This is presented in the Treatise, some 30 pages after his discussion of polygyny's value to women, in the following chapter and in a section about “price” rigidities in marriage. As I show in Figure 1 an effective price ceiling in a market for wives could prevent the market equilibrium price from being reached.Footnote ¹² In this case it is possible that women's share of marital income under polygyny will be lower than under monogamy to the extent that polygyny is accompanied with a substantial price ceiling but monogamy is not. For example, in Figure 1 married women's income under “polygyny + price ceiling” f_c is lower than their income f_m assuming a competitive equilibrium under monogamy without a price ceiling. Women are also worse off under polygyny if there is a price ceiling on their marital income under both polygyny and monogamy, but the gap between equilibrium price and price ceiling is sufficiently larger under polygyny than under monogamy.

The question is then whether under polygyny women are likely to obtain their market value f_p or whether they will get a marital income that has been substantially capped by a price ceiling, perhaps as low as f_c < f_m, implying that women are better off under monogamy than under polygyny. Inspired by Guttentag and Secord's (1983) ideas on sex ratios and Becker's analyses of “price ceilings”, I wrote in 1993 that where polygyny is permitted men are more likely to deprive women from the share of marital income that they would obtain if they had access to their market value (Grossbard-Shechtman Reference Grossbard-Shechtman1993, Ch. 11). In 2010, I testified accordingly before the Supreme Court of British Columbia in Canada when it considered the legalization of polygyny (Bramham Reference Bramham2010), concluding that polygyny is likely to harm women.

Interestingly, Becker himself recognized that polygynous societies may cap women's share of marital income more than monogamous ones. In the chapter following the chapter on polygyny, Becker (Reference Becker1981 pp. 86–87) writes that “the difference between actual and equilibrium income is probably greater when (women’s) equilibrium income is a larger share of marital output (“a larger share (of marital output) may not be as readily appropriated by wives”, (my italics)) . . . as in the following situations: in societies with a larger supply of men relative to women; . . . in societies with a higher incidence of polygyny; and in patrilineal societies . . . because husbands have more control over the division of marital output, especially over children, in such societies.” However, in that later chapter Becker's focus was on explaining the institution of bride price, and he does not state how price ceilings are likely to hurt women's relative wellbeing under polygyny.

The incidence of bride price (paid by men or their relatives prior to marriage) and dowry (paid by women or their relatives prior to marriage) is positively correlated to the incidence of polygyny. Grossbard (Reference Grossbard1978a, 1978b) documents that correlation. Grossbard (Reference Grossbard1978a, Reference Grossbard1978b) and Becker (Reference Becker1981, p. 56) used that correlation as evidence that married women are better off in polygyny than in monogamy, assuming that if the price of wives is higher, men will pay more both during marriage and before marriage in the form of a bride price.

A more complete recent study has confirmed the positive correlation between bride price and polygyny (Tertilt Reference Tertilt2005).Footnote ¹³ However today I think that far from demonstrating that married women are better off under polygyny than under monogamy, that correlation provides evidence to the contrary. Under polygyny women are worse-off than under monogamy because under polygyny, it is more likely that price ceilings have been placed on their access to marital income: the institution of bride price could be a signal that such ceilings have been imposed and there is a shortage of brides that bride prices help resolve.Footnote ¹⁴

Becker (Reference Becker1981, Ch. 4, p. 87) hints to such alternative causality linking bride prices and polygyny: “the difference between actual and equilibrium income of wives is probably greater when their equilibrium income is a larger share of marital output (..). Therefore the frequency and magnitude of bride prices should be greater.. in societies with a higher incidence of polygyny.” Becker does not explain why wives’ actual income would diverge more from equilibrium income when equilibrium income is higher (possibly due to polygyny). One explanation follows from one of the reasons that Becker gives for why actual women's share of marital income is below market equilibrium: men, having “sometimes been given legal control over the assignment of shares (of marital output)” (Becker Reference Becker1981, p. 86, citing Weitzman Reference Weitzman1974, emphasis mine), may have more incentives to use their legal control to place a ceiling on women's marital income when women's relative equilibrium income in marriage is higher (for example due to polygyny). The excess demand for wives (aka shortage of wives) resulting from a price ceiling may lead to a bride price system. One can draw an analogy between rent controls and ceilings on women's price: both create shortages. In the case of housing, prospective tenants often “bribe” landlords or current tenants into allowing them access to scarce and coveted rent-controlled housing. In the case of polygynous societies, bride prices allow men to gain access to scarce, highly valued women.

What social scientists also need to explain is the political economy of both polygyny and ceilings on women's marital incomes. While there is a literature on the political economy of polygamy, it deals mostly with the emergence and disappearance of polygyny regimes (e.g. Grossbard Reference Grossbard1978b; Becker Reference Becker1981; Kanazawa and Still Reference Kanazawa and Still1999; de la Croix and Mariani Reference de la Croix and Marianiforthcoming), not with explaining price ceilings on women's marital income as a function of polygyny. In these models, rich men and poor or uneducated women are more likely to lobby for polygyny, whereas poor men and rich or educated women are likely to oppose polygyny. The same rich men who would “lobby” for polygyny's legalization would also prefer price ceilings on women's marital income that redistribute income in their favor.Footnote ¹⁵ However, while some women (the least productive ones, who may otherwise remain unmarried) may support polygyny, one does not expect any women to “vote” for caps on their own share of marital income. Wives’ lower appropriations under polygyny (using Becker's language) may not be out of choice but a result of men controlling the relevant political and religious institutions to their own advantage.

It follows that, relative to monogamous societies, societies that allow polygyny are likely to also have limited women's influence in politics and society (Guttentag and Secord Reference Guttentag and Secord1983). If polygyny was instituted and price ceilings are preventing women from enjoying their high market value it indicates that women may not have the power to oppose the combination of polygyny and price ceilings that benefits rich men. Poor men who benefit from ceilings on women's share of marital income may form coalitions with rich men and agree to a system that has such ceilings and allows polygyny.

For the same reasons that polygyny is associated with caps on women's married income and the incidence of bride price it is also associated with other institutions that tend to harm women (Grossbard Reference Grossbard, Bennion and Joffe2015b). For example, polygynous societies also tend to: (1) allow child marriages which curtail freedom to choose mates and tends to apply to girls more than boys (see Bramham Reference Bramham2009 for Canada), (2) encourage female genital mutilation (lowering women's sexual drive and thereby making it easier for polygynous husbands to satisfy all of their wives sexually, see Rahman and Toubia Reference Rahman and Toubia2000), and (3) limit women's ability to earn income in the labor force. In African and Asian polygynous societies women are often secluded into “purdah” (see Cohen Reference Cohen1971); the polygynous Fundamentalist Latter Day Saints communities in North America are often isolated and offer very limited employment opportunities to women (Bramham Reference Bramham2009). Anderson (Reference Anderson2007) reports that bride price has been linked to domestic violence against women. Given the positive association between bride price and polygyny, domestic violence could be associated with polygyny, with bride price, or with both. Future research will hopefully be able to establish causalities.