The standard meaning of “unintended consequences” today is unwelcome and unanticipated policy outcomes. As such, it fits well within organization theory, which tends to focus on organizational shortcomings rather than accomplishments (Stinchcombe 2001, pp. 1–17). In light of well-established theories such as “goal displacement,” “garbage-can” decision making, “institutionalization,” “isomorphism,” “bounded rationality,” and “muddling through,” it is hardly surprising that failure to anticipate unwelcome consequences is the rule rather than the exception in policy making. Students of bureaucracy theory are well prepared to accept this. But what about unintended yet anticipated effects?
Consider this example: official statistics show that China’s overall sex ratio at birth was 118 boys for 100 girls in 2010. “If the trend continues,” the director of National Population and Family Planning Commission stated at a press conference,22 “it will jeopardize gender equality, development of girls, lawful interests and rights of women, and the nation’s long-term development.” The female population deficit is often explained as an unintended consequence of China’s one-child policy (e.g., Shalev 2001; Ebenstein 2010; Legge and Zhao 2004). To assure male offspring under the constraint of the one-child policy, households practice “sex selection” (Ebenstein 2010, p. 5), which results in a national female population deficit. Sex selection is a household choice for the lesser of two evils that produces unintended outcomes (cf. Aya 2006, p. 118). But what about anticipation? If we think of the deficit as resulting from a multitude of household decisions, it is an “effect of aggregation” (Boudon 1982, pp. 139–140).23 There is no organization or design, only numerous separate households who prefer sons over daughters and act accordingly. In this situation, lack of anticipation is more or less a given, as in the afore-mentioned spontaneous order tradition.
But if the female deficit is an unintended consequence of the one-child policy, we invoke organized action and that changes the situational logic. The Chinese government introduced the one-child policy to curb population growth; the female population deficit is its unintended consequence. But lack of anticipation is hardly a given here. Ebenstein concludes that “encouraging or forcing people to change their fertility behavior without addressing their fundamental preferences may have unanticipated consequences” (2010, p. 31).24 But why presume ignorance here? Governments specialize in anticipation; is it really likely that the Chinese government was unaware of the mechanism described above and did not foresee its consequences?
According to Greenhalgh (2008, pp. 267–268), makers of the one-child policy and other government officials anticipated the female population deficit. But it did not keep them from pursuing the policy. Instead they banned the issue of sex ratio imbalance from public debate and stifled research on it. “[S]cholars were forbidden to address the question of female infanticide or even the SRB [sex ratio at birth]” (ibid., p. 267). But “party propagandists were well aware of the possibility that . . . rural couples might abandon or even kill their infant daughters” (ibid., p. 356 fn.). Indeed cadres in rural areas were instructed to teach gender equality and to urge the population to overcome old ideas about the superiority of sons. China’s female population deficit, then, is better characterized as an unintended but anticipated consequence.
Consider another example. Asari et al. (2008) write about what they see as one of the major problems facing contemporary British society: “the failure to produce a discourse that integrates various ethnic groups under the umbrella of a common British identity” (2008, p. 1). The pursuit of multiculturalism, they write, “reinforces ethno-cultural elements of identity. Indeed, the way multiculturalism has been implemented in Britain has proven problematic, with the unintended consequence of causing segregation and disunity” (ibid., p. 13). Left unqualified, “unintended” in conventional usage suggests lack of anticipation. But the risk of segregation has been a standard critique of multiculturalism since its inception, a risk policy makers around the world are keenly aware of (De Zwart 2000, 2005; Schraml 2011).25 Segregation is an unwelcome but anticipated side effect: it is permitted because it is traded off against intended effects such as managing immediate crises and promoting equal cultural recognition.26
The analysis of unintended consequences in public sector reform, Guy Peters writes, makes “reformers appear terribly naïve so that they would not understand just what they are doing, but generally these reformers [simply have] to make difficult choices in complex situations” (2007, p. 23). What makes reformers appear naïve, I would add, is the habit of using unintended as a synonym for unanticipated, whereas in reality reformers must often make “difficult” choices—difficult precisely because they foresee unwelcome effects. Conflating “unintended” and “unanticipated” obscures this.
that have languished over the last half century under insecure property rights and economic institutions, impoverishing much of their populations, did not allow this to happen because they thought it was good economics [which would make impoverishment an unintended and unanticipated consequence, FdZ]; they did so because they could get away with it and enrich themselves at the expense of the rest, or because they thought it was good politics, a way of keeping themselves in power by buying the support of crucial groups or elites. (ibid., p. 66)
policy of ‘one more step’—each new step always promising the success which the previous last step had also promised but had unaccountably failed to deliver . . . lured the United States deeper into the morass. . . . We have achieved our present entanglement not after due and deliberate consideration, but through a series of small decisions; . . . each step led only to the next, until we find ourselves entrapped in that nightmare of American strategist, a land war in Asia. (Schlessinger [Jr. (1968)] in Ellsberg 1972, pp. 49–50)
This theory, Ellsberg notes, seemed plausible to so many because it “accords with the major, widespread presumption that the ‘nightmare’ outcome must have been unforeseen even as a strong possibility by those who made the decisions leading toward it; or else they would have drawn back, or at least warned the public of the demands ahead” (ibid., p. 50, italics in original). But Ellsberg’s research shows that presumption entirely wrong; the quagmire model is a myth, or, in terms of this article, the nightmare outcome may be unintended but it is not unanticipated. The Presidents that made the decisions leading to the “nightmare outcome” did so after having been told, in striking detail, by military and civilian specialists, what this outcome would be. Rather than the US Government lacking foresight and consequently stumbling into quicksand, “one sees, repeatedly, a leader striding with his eyes open into what he sees as quicksand, increasing his efforts and carrying his followers deeper in. Why? Presumably, because he sees no alternative . . . or because the alternatives seem even more threatening, worse in the short run” (ibid., p. 79).
Unintended but anticipated outcomes often concern controversial and politically sensitive issues, and the connotation of “unanticipated” that sticks to “unintended” makes it possible to expose, discuss, or correct such issues without imputing blame or getting into painful discussions about responsibility. “Looking at where their policies and tactics have brought us so far,” Ellsberg writes, “it is easy to understand why the past four Presidents would want . . . to conceal and deprecate their own foreknowledge and intentions. . . . Presidents and their partisans find comfort and political safety in the quicksand image” (ibid., pp. 127, 131).
The disentangling of unintended and unanticipated consequences foregrounds questions of justification and responsibility, illustrated by a debate among moral philosophers on the “double effect,” or the foreseeable causation of harm. At issue is the question of whether a person may “licitly perform an action that he foresees will produce a good effect and a bad effect” (Mangan 1949, p. 43). The principle of double effect—introduced by Thomas Aquinas to justify self-defense28--provides a moral justification for such acts if four conditions are met: “1. that the action in itself from its very object be good or at least indifferent; 2. that the good effect and not the evil effect be intended; 3. that the good effect be not produced by means of the evil effect; 4. that there be a proportionately grave reason for permitting the evil effect” (ibid.).
The principle of double effect is widely accepted as a moral guideline (Boyle 1980).29 A classic illustration condemns the terror bomber but condones the tactical precision bomber, though both anticipate an equal number of civilian casualties. A terror bomber aims at civilians to cause terror; civilian casualties result from his intentions. The tactical bomber intends to take out enemy military targets; civilian casualties are an unintended but anticipated side-effect. The principle of double effect defines terror bombing as morally impermissible but permits tactical bombing.30 Some authors, however, are skeptical about the moral significance of the difference between what is intended and what is merely foreseen (McIntyre 2001, 2011); others doubt the extent to which the doctrine of double effect actually codifies moral intuition (Otsuka 2008). As space does not allow more detailed discussion, I mention this here to show that the distinction between intention and anticipation is clearly a question in ethics. But in social science this distinction has been blurred through conceptual conflation.
This article is about the sociological concept. For the novel, see Unintended Consequences (novel).
In the social sciences, unintended consequences (sometimes unanticipated consequences or unforeseen consequences) are outcomes that are not the ones foreseen and intended by a purposeful action. The term was popularised in the twentieth century by American sociologistRobert K. Merton.
Unintended consequences can be grouped into three types:
- Unexpected benefit: A positive unexpected benefit (also referred to as luck, serendipity or a windfall).
- Unexpected drawback: An unexpected detriment occurring in addition to the desired effect of the policy (e.g., while irrigation schemes provide people with water for agriculture, they can increase waterborne diseases that have devastating health effects, such as schistosomiasis).
- Perverse result: A perverse effect contrary to what was originally intended (when an intended solution makes a problem worse). This is sometimes referred to as 'backfire'.
The idea of unintended consequences dates back at least to John Locke who discussed the unintended consequences of interest rateregulation in his letter to Sir John Somers, Member of Parliament. The idea was also discussed by Adam Smith, the Scottish Enlightenment, and consequentialism (judging by results). However, it was the sociologist Robert K. Merton who popularised this concept in the twentieth century.
In his 1936 paper, "The Unanticipated Consequences of Purposive Social Action", Merton tried to apply a systematic analysis to the problem of unintended consequences of deliberate acts intended to cause social change. He emphasized that his term "purposive action... [is exclusively] concerned with 'conduct' as distinct from 'behavior.' That is, with action that involves motives and consequently a choice between various alternatives". Merton's usage included deviations from what Max Weber defined as rational social action: instrumentally rational and value rational. Merton also stated that "no blanket statement categorically affirming or denying the practical feasibility of all social planning is warranted."
More recently, the law of unintended consequences has come to be used as an adage or idiomatic warning that an intervention in a complex system tends to create unanticipated and often undesirable outcomes. Akin to Murphy's law, it is commonly used as a wry or humorous warning against the hubristic belief that humans can fully control the world around them.
Possible causes of unintended consequences include the world's inherent complexity (parts of a system responding to changes in the environment), perverse incentives, human stupidity, self-deception, failure to account for human nature, or other cognitive or emotional biases. As a sub-component of complexity (in the scientific sense), the chaotic nature of the universe—and especially its quality of having small, apparently insignificant changes with far-reaching effects (e.g., the butterfly effect)—applies.
Robert K. Merton listed five possible causes of unanticipated consequences in 1936:
- Ignorance, making it impossible to anticipate everything, thereby leading to incomplete analysis
- Errors in analysis of the problem or following habits that worked in the past but may not apply to the current situation
- Immediate interests overriding long-term interests
- Basic values which may require or prohibit certain actions even if the long-term result might be unfavourable (these long-term consequences may eventually cause changes in basic values)
- Self-defeating prophecy, or, the fear of some consequence which drives people to find solutions before the problem occurs, thus the non-occurrence of the problem is not anticipated
The creation of "no-man's lands" during the Cold War, in places such as the border between Eastern and Western Europe, and the Korean Demilitarized Zone, has led to large natural habitats.
The sinking of ships in shallow waters during wartime has created many artificial coral reefs, which can be scientifically valuable and have become an attraction for recreational divers. Retired ships have been purposely sunk in recent years, in an effort to replace coral reefs lost to global warming and other factors.
In medicine, most drugs have unintended consequences ('side effects') associated with their use. However, some are beneficial. For instance, aspirin, a pain reliever, is also an anticoagulant that can help prevent heart attacks and reduce the severity and damage from thrombotic strokes. The existence of beneficial side effects also leads to off-label use—prescription or use of a drug for an unlicensed purpose. Famously, the drug Viagra was developed to lower blood pressure, with its use for treating erectile dysfunction being discovered as a side effect in clinical trials.
The implementation of a profanity filter by AOL in 1996 had the unintended consequence of blocking residents of Scunthorpe, North Lincolnshire, England from creating accounts due to a false positive. The accidental censorship of innocent language, known as the Scunthorpe problem, has been repeated and widely documented.
The objective of microfinance initiatives is to foster micro-entrepreneurs but an unintended consequence can be informal intermediation: That is, some entrepreneurial borrowers become informal intermediaries between microfinance initiatives and poorer micro-entrepreneurs. Those who more easily qualify for microfinance split loans into smaller credit to poorer borrowers. Informal intermediation ranges from casual intermediaries at the good or benign end of the spectrum to 'loan sharks' at the professional and sometimes criminal end of the spectrum.
In 1990, the Australian state of Victoria made safety helmets mandatory for all bicycle riders. While there was a reduction in the number of head injuries, there was also an unintended reduction in the number of juvenile cyclists—fewer cyclists obviously leads to fewer injuries, assuming all else being equal. The risk of death and serious injury per cyclist seems to have increased, possibly due to risk compensation. Research by Vulcan, et al. found that the reduction in juvenile cyclists was because the youths considered wearing a bicycle helmet unfashionable. A health-benefit model developed at Macquarie University in Sydney suggests that, while helmet use reduces "the risk of head or brain injury by approximately two-thirds or more", the decrease in exercise caused by reduced cycling as a result of helmet laws is counterproductive in terms of net health.
Prohibition in the 1920s United States, originally enacted to suppress the alcohol trade, drove many small-time alcohol suppliers out of business and consolidated the hold of large-scale organized crime over the illegal alcohol industry. Since alcohol was still popular, criminal organisations producing alcohol were well-funded and hence also increased their other activities. Similarly, the War on Drugs, intended to suppress the illegal drug trade, instead increased the power and profitability of drug cartels who became the primary source of the products.
In CIAjargon, "blowback" describes the unintended, undesirable consequences of covert operations, such as the funding of the Afghan Mujahideen and the destabilization of Afghanistan contributing to the rise of the Taliban and Al-Qaeda.
The introduction of exotic animals and plants for food, for decorative purposes, or to control unwanted species often leads to more harm than good done by the introduced species.
- The introduction of rabbits in Australia and New Zealand for food was followed by an explosive growth in the rabbit population; rabbits have become a major feralpest in these countries.
- Cane toads, introduced into Australia to control canefield pests, were unsuccessful and have become a major pest in their own right.
- Kudzu, introduced to the US as an ornamental plant in 1876 and later used to prevent erosion in earthworks, has become a major problem in the Southeastern United States. Kudzu has displaced native plants and has effectively taken over significant portions of land.
The protection of the steel industry in the United States reduced production of steel in the United States, increased costs to users, and increased unemployment in associated industries.
See also: Perverse incentive and Perverse subsidies
In 2003, Barbra Streisand unsuccessfully sued Kenneth Adelman and Pictopia.com for posting a photograph of her home online. Before the lawsuit had been filed, only 6 people had downloaded the file, two of them Streisand's attorneys. The lawsuit drew attention to the image, resulting in 420,000 people visiting the site. The Streisand effect was named after this incident, describing when an attempt to censor or remove a certain piece of information instead draws attention to the material being suppressed, resulting in the material instead becoming widely known, reported on, and distributed.
Passenger-side airbags in motorcars were intended as a safety feature, but led to an increase in child fatalities in the mid-1990s as small children were being hit by deploying airbags during collisions. The supposed solution to this problem, moving the child seat to the back of the vehicle, led to an increase in the number of children forgotten in unattended vehicles, some of whom died under extreme temperature conditions.
Risk compensation, or the Peltzman effect, occurs after implementation of safety measures intended to reduce injury or death (e.g. bike helmets, seatbelts, etc.). People may feel safer than they really are and take additional risks which they would not have taken without the safety measures in place. This may result in no change, or even an increase, in morbidity or mortality, rather than a decrease as intended.
The British government, concerned about the number of venomous cobra snakes in Delhi, offered a bounty for every dead cobra. This was a successful strategy as large numbers of snakes were killed for the reward, but eventually enterprising people began to breed cobras for the income. When the government became aware of this, they scrapped the reward program, causing the cobra breeders to set the now-worthless snakes free. As a result, the wild cobra population further increased. The apparent solution for the problem made the situation even worse, becoming known as the Cobra effect.
Theobald Mathew's temperance campaign in 19th-century Ireland (in which thousands of people vowed never to drink alcohol again) led to the consumption of diethyl ether, an intoxicant much more dangerous due to its high flammability, by those seeking to become intoxicated without breaking the letter of their pledge.
It was thought that adding south-facing conservatories to British houses would reduce energy consumption by providing extra insulation and warmth from the sun. However, people tended to use the conservatories as living areas, installing heating and ultimately increasing overall energy consumption.
A reward for lost nets found along the Normandy coast, offered by the French government between 1980 and 1981, resulted in people vandalizing nets to collect the reward.
Beginning in the 1940s and continuing into the 1960s, the Federal Canadian government gave the Catholic church in Quebec $2.25 per day per psychiatric patient for their cost of care, but only $0.75 a day per orphan. The perverse result is that the orphan children were diagnosed as mentally ill so the church could receive the larger amount of money. This psychiatric misdiagnosis affected up to 20,000 people, and the children are known as the Duplessis Orphans.
There have been attempts to curb the consumption of sugary beverages by imposing a tax on them. However, a study found that the reduced consumption was only temporary. Also, there was an increase in the consumption of beer among households.
The New Jersey Childproof Handgun Law, which was intended to protect children from accidental discharge of firearms by forcing all future firearms sold in New Jersey to contain "smart" safety features, has delayed, if not stopped entirely, the introduction of such firearms to New Jersey markets. The wording of the law caused significant public backlash, fuelled by gun rights lobbyists, and several shop owners offering such guns received death threats and stopped stocking them In 2014, 12 years after the law was passed, it was suggested the law be repealed if gun rights lobbyists agree not to resist the introduction of "smart" firearms.
Drug prohibition can lead drug traffickers to prefer stronger, more dangerous substances, that can be more easily smuggled and distributed than other, less concentrated substances.
Abstinence-only sex education has been shown to increase teenage pregnancy rates, rather than reduce them, when compared to either comprehensive sex education or no sex education at all.
Increasing usage of search engines, also including recent image search features, has contributed in the ease of which media is consumed. Some abnormalities in usage may have shifted preferences for, Pornographic film actors, as the producers began using common search queries or tags to label the actors in new roles.
Most modern technologies have negative consequences that are both unavoidable and unpredictable. For example, almost all environmental problems, from chemical pollution to global warming, are the unexpected consequences of the application of modern technologies. Traffic congestion, deaths and injuries from car accidents, air pollution, and global warming are unintended consequences of the invention and large scale adoption of the automobile. Hospital infections are the unexpected side-effect of antibiotic resistance, and even human overpopulation is the side effect of various technological (i.e., agricultural and industrial) revolutions.
Because of the complexity of ecosystems, deliberate changes to an ecosystem or other environmental interventions will often have (usually negative) unintended consequences. Sometimes, these effects cause permanent irreversible changes. Examples include:
- During the Four Pests Campaign a killing of sparrows was declared. Chinese leaders later realized that sparrows ate a large amount of insects, as well as grains. Rather than being increased, rice yields after the campaign were substantially decreased.
- During the Great Plague of London a killing of dogs and cats was declared. The animals could have helped keep in check the rat population carrying the fleas which transmitted the disease.
- The installation of smokestacks to decrease pollution in local areas, resulting in spread of pollution at a higher altitude, and acid rain on an international scale.
- After about 1900, public demand led the federal government to fight forest fires in the American West, and set aside land as national forests and parks to protect them from fires. This policy led to fewer fires, but also led to growth conditions such that, when fires did occur, they were much larger and more damaging. Modern research suggests that this policy was misguided, and that a certain level of wildfires is a natural and important part of forest ecology.
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