(3) How general law determines the outcomes of individual cases (or not), and what this tells us about legal research

At the end of the previous class, students were confronted with the following statement, and had to decide whether they agree or disagree:

The majority of individual legal cases has one correct solution that follows from higher-ranking law.

The group of students that has agreed with this statement is then asked a follow-up question:

What do you believe is the job of judges if there usually is only one correct solution to individual legal cases?
“If there is one correct solution to individual legal cases that follows from higher-ranking law, what the hell is my job?”

The group that disagreed with the first statement is then asked this question:

What do you think is the point of having a legal system when most individual cases are not determined by it?

These questions point towards an apparent contradiction:

  • On the one hand it is well-known that the legal system allows for a lot of maneuvering; attorneys can use procedural strategies or smart arguments to win the case for their client; laws can often be interpreted in different ways, etc. We can thus speak of the underdetermined character of the legal system, by which we mean that the outcomes in specific cases can often not be readily deduced from the higher-ranking law.
  • On the other hand there is a general expectation that the legal system should ensure a certain stability and predictability of outcomes. This is one important aspect of the principle of “legal certainty.”

But if law is underdetermined, i.e., if individual outcomes cannot directly be deduced from higher-ranking law, does this not undermine legal certainty? We will first explore both sides of this apparent contradiction, and then propose a way how to deal with it.

The “indeterminacy” of law

The students were assigned to read a short text by Hans Kelsen: On the Theory of Interpretation. First, the students were asked to consider the following examples:

  • In 1971, it was ruled that the prohibition of same-sex marriage was constitutional in the US. In 2015, the US Supreme Court ruled in Obergefell v Hodges that the opposite was the case. → How can the US Constitution allow something, and then prohibit the same thing 40 years later, despite the fact that it has not been amended during that time (except in procedural aspects not relevant for this question)?
  • In 2009, the recognition rate of asylum applications by Iraqis in Germany was 70%, whereas it was only 7% in Sweden. → How can the recognition rate of individuals from the same country differ so significantly if the applicable Swedish and German legal regimes are comparable (both being determined in the relevant aspects by international and EU law)?

Both cases are examples for when individual legal decisions appear not to be fully determined by higher-ranking law in a certain significant aspect: the US Supreme Court could have plausibly ruled differently (as the 4 judges who dissented in fact believed it should), and the Swedish immigration officers could (presumably) often evaluate the asylum applications by Iraqis differently. The law is thus underdetermined in important respects, as general norms usually do not not fully determine the outcomes in individual cases.

What are the causes of this indeterminacy? There are at least three relevant factors at play:

  • First, law often grants a significant scope of (explicit) discretion to those charged with the application of the law. For example, the Austrian Sicherheitspolizeigesetz (SGP) authorizes the police to interfere with an individual’s legal rights (e.g. by applying force) if this is necessary to protect other legal rights, and if the damage that can thereby be prevented clearly and significantly outweighs the damage caused by this interference (§32). Such broad definition of a police agent’s competence clearly leaves a lot of discretionary choice to her. Obviously this significant discretion has been granted on purpose, as the lawmakers cannot plausibly foresee and regulate all possible scenarios that a police agent may encounter; within a frame defined by the law, the police agent is authorized to follow her own best judgment. However, this implies the possibility that different police agents may evaluate comparable situations very differently, even though they act on the basis of the same general norm. Consequently, the way Austrian police agent apply §32 is not fully determined by the SGP itself; more generally speaking, individual outcomes cannot be deduced directly from the higher-ranking law. Kelsen made this point as follows:
In the relation between statute and judicial decision or administrative act, procedural regulation and regulation of the content of the future norm are balanced; just as the procedure for creating the individual norm is determined, so likewise the content of the individual norm (in the substantive law, [including] civil law, criminal law, and administrative law) is determined. This determination, however, is never complete, for a norm cannot be binding with respect to every detail of the act putting it into practice. There must always remain a range of discretion, sometimes wider, sometimes narrower, so that the higher-level norm, in relation to the act implementing it (an act of lower-level norm creation or of pure implementation), has simply the character of a frame to be filled in by way of the act. (p. 128).
  • Second, law is just a specific way of using language; and just like in casual communication, words and sentences can always be interpreted in different ways, and they alter their meaning in different legal and factual contexts. Kelsen wrote in that regard:
Indeterminacy of the legal act can also be the unintended consequence of properties of the norm to be implemented by the act in question. First of all, there is the ambiguity of a word or a phrase used in expressing the norm; the linguistic sense of the norm is not unequivocal, and whoever is to implement the norm is faced with several possible readings. (p. 129)
  • Third, the interpretation and application of law always involves the appreciation and evaluation of non-legal facts, and lawyers may legitimately disagree on them. For example, according to the Austrian Asylgesetz an individual is to be granted asylum in Austria if she can convince the authorities that she is at risk of persecution in her home country. Whether this is found to be the case depends on the authorities’ knowledge, understanding and evaluation of the political situation in the home country, and on their evaluation of whether her case is credible, which in turn may be influenced by conscious or unconscious biases held by the immigration officer.

Let us now return to our earlier examples. The US Supreme Court’s decision in Obergefell is based on an interpretation of the 14th Amendment of the US Constitution, which holds:

All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside. No State shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States; nor shall any State deprive any person of life, liberty, or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws.

The provision was enacted in the wake of the US Civil War with the objective to protect African Americans from discrimination by the Southern states, but is manifestly phrased in much more general terms. Whether a prohibition of same-sex marriage also constitutes discrimination in the sense of the Amendment is simply not clear from its text, context or history: it can be interpreted differently. Thus, the Amendment must be considered to be underdetermined (as it allows for radically different interpretations), and the US Supreme Court has significant discretion in interpreting it. Regarding the second example, the vast differences in recognition rates similarly indicate that the authorities in the various European countries have significant discretion in evaluating the factual situation of asylum seekers, and that the same fact (i.e., the political situation in Iraq) can be judged very differently.

Based on these two examples we can propose that most, if not all, law is underdetermined, because it always implies discretionary choices (though norms can be underdetermined to different degrees). If there are different interpretations of a norm possible, which of the different possible interpretations should be chosen by the authority applying the norm? Kelsen:

Interpreting a statute, then, leads not necessarily to a single decision as the only correct decision but possibly to several decisions, all of them of equal standing measured solely against the norm to be applied, even if only a single one of them becomes, in the act of the judicial decision, positive law. (p 129)

Kelsen emphasizes that, if different interpretations are possible, positive law does not hold the answer as to which interpretation should be chosen. This is a logical implication of the very fact that different interpretations of the law are possible. In such case, the relevant authority has discretion to choose between the different possible interpretations. Because the law does not further guide how this discretion should be exercised, this choice is sometimes described as a “political” one. Kelsen:

From the standpoint of the positive law […] there is no criterion on the basis of which one of the possibilities given within the frame of the norm to be applied could be favoured over the other possibilities. In terms of the positive law, there is simply no method according to which only one of the several readings of a norm could be distinguished as ‘correct’ — assuming, of course, that several readings of the meaning of the norm are possible in the context of all other norms of the statute or of the legal system. (p. 130)

Thus, discretionary choice is present in the legal system every time when different interpretations of a provision are possible, which is most of the time (though to different degrees). Consequently, it cannot be assumed that the outcomes in individual legal cases can usually be readily deduced from the general norms. This leads Kelsen to conclude that “legal certainty”, if understood in that way, is an “illusion”:

The illusion of legal certainty is what traditional legal theory, wittingly or not, is striving to maintain. (p. 132)

In the (“political”) exercise of their discretion, lawmakers, judges and administrators may be guided by numerous possible factors. These include the following:

  • they can follow the common practice of their peers (e.g., a Swedish immigration officer passes similar decisions as her colleagues). This, in turn, can be justified on the grounds of ensuring consistency of comparable decisions in one jurisdiction. In practice, administrators will often do so (also) because it involves much less effort: the effort of writing and justifying a decision that deviates from the common practice of the colleagues will be significantly higher as compared to the effort necessary in simply following the colleagues’ example.
  • They can follow the precedents set by appellate courts (different to the US system, precedents are generally not considered to be legally binding in European jurisdictions). This can in turn be justified by reference to the benefits of consistency, or by the persuasive power of previous judgments (and, as in the previous case, involves less effort: if an administrator’s decision deviates from the practice accepted by appellate courts, she has to justify it well, as otherwise she risks that her decision will be invalidated upon appeal. This, in turn, might impact her career adversely).
  • They can also base their discretionary choice on good arguments that are not related to validity as such: they could draw from a specific ethical or political view, invoke various constitutional principles and regulatory objectives, engage in economic considerations, reflect on public opinion, etc. These arguments may be more or less convincing, but will usually not be unambiguous: even though, for example, certain constitutional principles may support a specific interpretation of a norm, most constitutions in fact encompass a broad spectrum of different, potentially conflicting principles, which could potentially be mobilized to support a different interpretation as well. Similarly, while e.g. an economic justification for interpreting the norm in a specific way may be found, this will often fail to be fully convincing either. Not only would it be questionable why economic considerations should override other regulatory concerns, but also — given the diversity of the economic discipline — will it often be possible to construct a reasonably plausible economic argument for some or all of the possible interpretations.
  • They may have personal preferences and conscious or unconscious biases that shape the exercise of their discretionary choice.

The indeterminacy thesis implies that the separation line that defines the legal system — namely the distinction between legal and non-legal communications — is always contestable. Precisely because the law — like any other communication — is always open to different interpretations, one interpreter may be of the opinion that, in a specific situation, only one interpretation is correct, whereas another disagrees, and identifies other possible interpretations. The first interpreter would then hold a specific outcome to be legally required, whereas the other would hold that this specific outcome is legally possible, but not required, and would be in need of justification through good arguments. The two thus disagree on the separation line between what the law unambiguously requires, and where “political” choice by the institution in question begins. This contestability of the law/politics divide is maybe the most important characteristic of legal discourse, and is routinely employed in a strategic form:

  • if you defend a certain measure, you portray it as following logically from the only correct interpretation of the law;
  • if you oppose a certain measure, you argue either that it is based on an incorrect interpretation of the law, or that it is based on one among multiple possible interpretations, and that the reasons given for choosing that specific interpretation are unconvincing.

To conclude this section, we can reiterate that the legal system can be considered to be underdetermined, which we defined as meaning that the outcomes of individual cases is often not fully determined by higher-ranking law. Rather, the application of law usually involves considerable discretion, which can be described as “political” in nature (the term is employed here merely in delineation from “legal”). In exercising this “political” choice, administrators or judges can be influenced by numerous factors, including (but not limited to) good arguments. The dividing line between what is legally required and what is merely legally possible is always contestable.

The predictability of legal outcomes

The principle of “legal certainty” is usually considered to be one of the main qualities of a legal system. We have already discussed that the legal system is often assumed to fulfill certain societal functions. We mentioned, for example, that the sociologist Niklas Luhmann defined its function as the stabilization of expectations over time. This, in turn, may be beneficial for the functioning of society as a whole or for certain parts of it. Obviously, a certain predictability of outcomes is necessary if the legal system is to fulfill such task. Consider the following propositions:

  • Proposition 1: General welfare may be improved if there is a reasonable expectation that, if individuals follow the laws known or accessible to them, they will not be targeted by the authorities.
  • Proposition 2: Traffic may be smoother and safer if there is a reasonable expectation that other drivers follow the traffic rules.
  • Proposition 3: The functioning of the market economy likely depends on the expectation that contractual obligations are usually fulfilled. It may be assumed that the possibility of parties to seek, if necessary, redress from a court, strengthens this expectation.

However, the (relative) predictability of outcomes does not necessarily stand in conflict with the underdetermined character of law that we identified in the previous section — consider the following observations:

  • ad 1: In most countries certain ethnic, religious or social groups cannot plausibly expect to remain unbothered by the authorities even if they abide by the law. For example, black and latino New Yorkers are subjected to random stop-and-frisk checks on the street to a significantly larger percentage than white New Yorkers. This is despite the fact that, as we already saw, the US Constitution’s 14th Amendment prohibits, inter alia, racial discrimination.
  • ad 2: Cyclists are obliged to give way to pedestrians at pedestrian crossings. However, the observable practice in Amsterdam is quite the contrary: pedestrians seem to be supposed to give way to cyclists even on a pedestrian crossing, and chaos tends to ensue if pedestrians do not wait until the bike has passed. I have never observed the authorities to police this rule, even though it appears quite unambiguous to me.
Cyclists in Amsterdam are fairly predictable, including that they consistently ignore certain traffic rules.

The first case shows that even a rule that appears quite straightforward in regard to the situation at stake may not lead to greater predictability of outcomes in the individual case. In the second case, the legal situation appears equally clear, and yet the reality on the streets of Amsterdam is a different one. In fact, the behavior of cyclists is largely predictable insofar as they can be expected not to follow (some of) the rules. The authorities’ practice is also fairly predictable insofar as one can reasonably expect them to abstain from policing them. Consequently, predictability of outcomes is not necessarily dependent on whether the law is highly determined or not.

“Indeterminacy” and “predictability”: different phenomena that require different research methods

Legal practitioners and scholars are obviously not only interested in the question of how many different valid interpretations of a norm exist and how broad the discretion of judges and administrators is (even though these are important questions as well), but also how institutions exercise their discretion in practice. While the two questions — which relate to the concepts of “indeterminacy” and “predictability”, respectively — are often addressed together in legal scholarship, they in fact concern different issues:

  • The discussion on the “indeterminacy” of law relates to the question of validity, i.e., whether a communication is “legal” within the context of a specific legal system.
  • By contrast, the discussion of “predictability” concerns a different type of question, namely whether regular individuals or legal professionals can predict, in practice, the content of future decisions in individual cases (or more generally the behavior of authorities).
This image shows a jurist engaged in her work, predicting legal outcomes.

In other words, the first question concerns how e.g. a court is required or authorized to act (legal obligation and discretion). The concept of “indeterminacy” merely describes the fact that there always is some degree of discretion. The second question deals with how an institution exercises this discretion in practice. Thus, the research objective is a different one, which also means that different research methods may be appropriate. The first question, as discussed in an earlier class, falls into the sphere of doctrinal legal scholarship, which employs the “legal method”, i.e., the interpretation of further legal communications to ascertain that a specific legal communication is valid according to the specific legal system in question. As discussed in the first class, the “legal method” researches the meaning of specific communications (namely “legal” communications) by means of interpretation (“hermeneutics”). It is thus comparable to other disciplines that employ hermeneutic tools (e.g. literature, theology, discourse analysis); however, it is concerned only with a specific type of communication, namely those that are “valid” under a specific legal system.

Regarding the predictability of outcomes, on the other hand, various methodical approaches are possible, as legal practice can be observed through the eyes of many different social sciences. Consider the following factors which could potentially shape the exercise of discretion by individuals and institutions:

  • Institutional dynamics: The Amsterdam police may have, consciously or through evolving practice, decided to focus their resources on the control on specific offenses, leaving certain other infractions unpoliced.
  • Psychology, socialization and political preferences of judges or administrators: The political orientation of judges and administrators as well as their socio-cultural background may, consciously or unconsciously, influence their decision-making. Seemingly profane factors may be relevant as well: a study has shown, for example, that judges tend to be more lenient after their lunch breaks.
Hangry judges pass harsh judgments.
  • Structure and composition of institutions: A labor court composed of worker and employer representatives may decide differently than the appellate body composed of professional judges; male judges may evaluate non-legal facts different than female ones; an institution with little support staff may issue different decisions than one that is well-equipped, etc.

Potential factors such as these cannot be researched with the “legal method”, which is solely concerned with the issue of validity; other disciplines — such as psychology, political science, sociology or economics — provide additional methods. The enforcement practice of the Dutch police could be studied with qualitative (e.g. study of publications, documents, or interviews) or quantitative means (e.g., comparison of the development of the number of police reports filed for different offenses, etc.). The study on “hangry” judges was written by psychologists on the basis of a quantitative analysis of court documents.

However, as we already discussed in a previous class, in practice mainstream legal scholars rarely venture into types of research that require methods that differ significantly from the hermeneutical approach. Thus, when legal scholars study the factors that shape the exercise of discretion e.g. by courts, they usually limit themselves to those that are accessible through the hermeneutical tools. Consider the following possible research questions:

  • If there are different possible interpretations of a specific norm, which one is employed by the institutions charged with the application of the law? Are different institutions applying conflicting interpretations?
  • Which arguments are mobilized in order to justify the use of a specific interpretation, if any?
  • If a norm explicitly grants discretionary choice to an institution, which factors does it consider, and which does it ignore? Does it tend to give preference to certain interests at the expense of others?
  • How do different judges portray victims of sexual violence? If specific gender stereotypes held by a judge can be identified (e.g. during the proceedings or in the court documents), does this shape the outcomes of the cases?

These questions all concern not the validity of a norm as such, but a specific aspect of the exercise of discretion by the institutions: they address the arguments and reasons these institutions forward to justify their interpretation of the norm and their exercise of discretionary (i.e., “political”) choice. These arguments are identified by hermeneutical means (i.e., interpretation), which nonetheless differ from the “legal method” insofar as the objective of research is different: not the validity of a decision, but the justifications forwarded by legal institutions for the exercise of discretion are researched. Consequently, one could speak of “(legal) discourse analysis” to describe such type of scholarship. In practice, legal scholarship usually does not distinguish between hermeneutical analysis for these two purposes, unless it is necessary for the author’s argument (which is the case when the current legal practice is criticized as an incorrect or unjustified interpretation of a norm).

Apart from hermeneutic analysis under the “legal method” itself, the “(legal) discourse analysis” of the arguments forwarded to justify discretionary choices has a privileged role in mainstream legal scholarship, for various reasons. Most notably, it is because legal decisions also encompass both, i.e., the arguments for why the decision is legally valid, and the arguments why, between equally valid interpretations, the court chooses one over the other. However, this sole focus on hermeneutical research (and the marginal presence of other research approaches in mainstream legal scholarship) may provide a distorted view of the the factors that actually shape legal outcomes, and an overestimation of the role good arguments play in that regard. I believe that the first question a judge or administrator asks when confronted with a new case is usually not “What is the applicable law, does it allow for different interpretations, and which argument support these different interpretations?” Instead, the first question often is: “How did previous judges and appellate courts decide similar cases?” Thus, the main reason a judge passes a certain judgment is because other courts have done so as well, and not necessarily because she finds the arguments so convincing. But the analysis of the arguments forwarded by the judge to support her judgment does not tell us about these other factors that may have influenced her decision. Consequently, the analysis of argumentation may, but does not necessarily help predict outcomes.


Here is an example for indeterminacy, predictability, and the method(s) employed by a legal scholar. The text is from Philippe Sands, and it deals with the question whether the International Court of Justice (ICJ), if it is confronted with a climate-change related case, would pass a “helpful” judgment.

You can see the following points:

  • For Sands, international law is undetermined on the issue of climate change: the ICJ could, in principle, pass all kinds of judgments. (we must presume that he used the “legal method” to come to this conclusion)
  • Then he moves towards a prognosis of the chances for a future “helpful” decision. Which methods does he use?
  • His old prognosis was that the ICJ would not pass a “helpful” judgment. It was based on his reading of previous ICJ cases (method: hermeneutics) — but the reading of the cases does not hold the complete answer. Rather, his prognosis requires further knowledge, namely about the institutional dynamics of the court (i.e., that they evaded difficult political questions in the past). Does he employ a specific method (e.g. from sociology, political science) for this? No! Rather, it is based on what could be termed “political speculation” (I mean this in a neutral sense, where “speculation” merely indicates that it is not guided by a specific research method. Sand’s speculation may still be plausible, even though he does not back it up with methodically guided research).
  • His new prognosis is different: he assumes that a number of factors have changed. Are these legal factors, i.e., did the law change? No! Rather, the political context has changed: countries like the US and China have shown more concern; the Pope has expressed his view on climate change; a Dutch court has passed a strong decision on climate change; and the science has become even more convincing. → this evaluation is still not guided by a specific scientific method, but continues to be “speculation”, namely on a) how these factors influence the institutional dynamic of the ICH, and b) which arguments the ICJ might find convincing for picking a “helpful” interpretation of international law.
  • We can see that Sands employed interpretation (hermeneutics) of international law, interpretation of previous ICJ cases, in conjunction with a broader evaluation of the political context, the latter not being guided by a specific research method.
  • International law is thus under-determined, and yet the ICJ appears to be predictable, at least to a certain extent.


We can sum up the previous discussion as follows:

  1. “Indeterminacy”, which we understood as the fact that individual decisions are rarely, if ever, fully determined by higher-ranking law, is a necessary aspect of the legal system. This implies nothing more (but also nothing less) than that discretionary choices form an integral part of the legal process. These choices (which are sometimes termed “political” because they are not further determined by higher-ranking law), can be, consciously or unconsciously, influenced by all kinds of factors. The dividing line between what is legally required and what is (merely) legally possible (i.e., the law/politics dividing line) is always contestable.
  2. “Legal certainty” is often considered to be a crucial quality of a legal system. An important aspect of this is whether individual legal decisions can be reasonably well predicted. It has been shown that “indeterminacy” and “predictability” concern different aspects of the legal system — the first relates to validity, the second to the institutional practice. The first is scrutinized with the hermeneutic instruments of the “legal method”. The same hermeneutic instruments can also be employed to study the arguments forwarded by institutions to justify their discretionary choices (we called this “legal discourse analysis”). However, the arguments forwarded for a certain decision may not be the factual cause of the outcome, so that a singular reliance on this form of scholarship may allow only for poor predictions.
  3. Other disciplines (such as sociology or psychology) may provide useful methods to scrutinize additional factors that potentially influence individual legal outcomes, and thereby increase predictability. In practice, however, legal scholarship engages mainly in hermeneutic studies. Research based on other methods tend to be conducted by non-legal researchers, and usually do not play a significant role in mainstream legal discourse. It has been argued that this singular focus of legal scholarship on hermeneutic instruments may be liable to misrepresent the relative importance of the different factors on the outcome, and in particular may overestimate the influence of good argumentation on the outcomes.