Arguments in Court - cyber crime and data protection cases

 Basic structure of legal argument

• (1) If conditions A, B and C are satisfied, then legal consequences X, Y and Z follow. (Major premise: legal rule)

• (2) Conditions A, B and C are satisfied (or not). (Minor Premise: the facts of the case)

• (3) Therefore, legal consequences X, Y and Z do (or do not) follow. (Conclusion: legal judgment in the case).

As I mentioned in part one, the first premise of this argument structure tends to get most of the attention in law schools. The second premise — establishing the actual facts of the case — tends to get rather less attention. This is unfortunate for at least three reasons.

First, in practice, establishing the facts of a case is often the most challenging aspect of a lawyer’s job. Lawyers have to interview clients to get their side of the story. They have to liaise with other potential witnesses to confirm (or disconfirm) this story. Sometimes they will need to elicit expert opinion, examine the locus in quo (scene of the crime/events) and any physical evidence, and so on. This can be a time-consuming and confusing process. What if the witness accounts vary? What if you have two experts with different opinions? Where does the truth lie?

Second, in practice, establishing the facts is often critical to winning a case. In most day-to-day legal disputes, the applicable legal rules are not in issue. The law is relatively clearcut. It’s only at the appeal court level that legal rules tend to be in dispute. Cases get appealed primarily because there is some disagreement over the applicable law. It is rare for appeal courts to reconsider the facts of case. So, in the vast majority of trials, it is establishing the facts that is crucial. Take, for example, a murder trial. The legal rules that govern murder cases are reasonably well-settled: to be guilty of murder one party must cause the death of another and must do this with intent to kill or cause grievous bodily harm. At trial, the critical issue is proving whether the accused party did in fact cause the death of another and whether they had the requisite intent to do so. If the accused accepts that they did, they might try to argue that they have a defence available to them such as self-defence or insanity. If they do, then it will need to be proven that they acted in self defence or met the requirements for legal insanity. It’s all really about the facts.

Third, the legal system has an unusual method of proving facts. This is particularly true in common law, adversarial systems (which is the type of legal system with which I am most familiar). Courts do not employ the best possible method of fact-finding. Instead, they adopt a rule-governed procedure for establishing facts that tries to balance the rights of the parties to the case against both administrative efficiency and the need to know the truth. There is a whole body of law — Evidence Law — dedicated to the arcana of legal proof. It’s both an interesting and perplexing field of inquiry — one that has both intrigued and excited commentators for centuries.

I cannot do justice to all the complexities of proving facts in what follows. Instead, I will offer a brief overview of some of the more important aspects of this process. I’ll start with a description of the key features of the legal method for proving facts. I’ll then discuss an analytical technique that people might find useful when trying to defend or critique the second premise of legal argument. I’ll use the infamous OJ Simpson trial to illustrate this technique. I’ll follow this up with a list of common errors that arise when trying to prove facts in law (the so-called ‘prosecutor’s fallacy’ being the most important). And I’ll conclude by outlining some critiques of the adversarial method of proving facts.

1. Key Features of Legal Proof

As mentioned, the legal method of proving facts is unusual. It’s not like science, or history, or any other field of empirical inquiry. I can think of no better way of highlighting this than to simply list some key features of the system. Some of these are more unusual than others.

Legal fact-finding is primarily retrospective: Lawyers and judges are usually trying to find out what happened in the past in order to figure out whether a legal rule does or does not apply to that past event. Sometimes, they engage in predictive inquiries. For example, policy-based arguments in law are often premised on the predicted consequences of following a certain legal rule. Similarly, some kinds of legal hearing, such as probation hearings or preventive detention hearings, are premised on predictions. Still, for the most part, legal fact-finding is aimed at past events. Did the accused murder the deceased? Did my client really say ‘X’ during the contractual negotiations? And so on.

Legal fact-finding is norm-directed:Lawyers and judges are not trying to find out exactly what happened in the past. Their goal is not to establish what the truth is. Their goal is to determine whether certain conditions — as set down in a particular legal rule — have been satisfied. So the fact-finding mission is always directed by the conditions set down in the relevant legal norm. Sometimes lawyers might engage in a more general form of fact-finding. For instance, if you are not sure whether your client has a good case to make, you might like to engage in a very expansive inquiry into past events to see if something stands out, but for the most part the inquiry is a narrow one, dictated by the conditions in the legal rule. At trial, this narrowness becomes particularly important as you are only allowed to introduce evidence that is relevant,/i> to the case at hand. You can’t go fishing for evidence that might be relevant and you can’t pursue tangential factual issues that are not relevant to the case simply to confuse jurors or judges. You have to stick to proving or disputing the conditions set down in the legal rule.

Legal fact-finding is adversarial (in common law systems): Lawyers defend different sides of a legal dispute. Under professional codes of ethics, they are supposed to do this zealously. Judges and juries listen to their arguments. This can result in a highly polarised and sometimes confusing fact-finding process. Lawyers will look for evidence that supports their side of the case and dismiss evidence that does not. They will call expert witnesses that support their view and not the other side’s. This is justified on the grounds that the truth may emerge when we triangulate from these biased perspectives but, as I will point out later on, this is something for which many commentators critique the adversarial system. There is a different approach in non-adversarial system. For instance, in France judges play a key role in investigating the facts of a case. At trial, they are the ones that question witnesses and elicit testimony. The lawyers take a backseat. Sometimes this is defended on the grounds that it results in a more dispassionate and less biased form of inquiry but this is debatable given the political and social role of such judges, and the fact that everyone has some biases of their own. Indeed, the inquisitorial system may amplify the biases of a single person.

Legal fact-finding is heavily testimony-dependent: Whenever a lawyer is trying to prove a fact at trial, they have to get a witness to testify to this fact. This can include eyewitnesses (people who witnessed the events at issue in the trial) or expert witnesses (people who investigated physical or forensic evidence that is relevant to the case). The dependence on testimony can be hard for people to wrap their heads around. Although physical evidence (e.g. written documents, murder weapons, blood-spattered clothes etc) is often very important in legal fact-finding, you cannot present it by itself. You typically have to get a witness to testify as to the details of that evidence (confirming that it has not been tampered with etc).

Legal Fact-Finding is probabilistic: Nothing is ever certain in life but this is particularly true in law. Lawyers and judges are not looking for irrefutable proof of certain facts. They are, instead, looking for proof that meets a certain standard. In civil (non-criminal trials), facts must be proved ‘on the balance of probabilities’, i.e. they must be more probable than not. In criminal trials, they must be proved ‘beyond reasonable doubt’. What this means, in statistical terms, is unclear. The term ‘reasonable doubt’ is vague. Some people might view it as proving someting is 75% likely to have occurred; others may view it as 90%+. There are some interesting studies on this (LINK). They are not important right now. The important point is that legal proof is probabilistic and so, in order to be rationally warranted, legal fact-finders ought to follow the basic principles of probability theory when conducting their inquiries. This doesn’t mean they have to be numerical and precise in their approach, but simply that they should adopt a mode of reasoning about facts that is consistent with the probability calculus. I’ll discuss this in more detail below.

Legal fact-finding is guided by presumptions and burdens of proof (in an adversarial system): Sometimes certain facts do not have to be proved; they are simply presumed to be true. Some of these presumptions are rebuttable — i.e. evidence can be introduced to suggest that what was presumed to be true is not, in fact, true — sometimes they are not. The best known presumption in law is, of course, the presumption of innocence in criminal law. All criminal defendants are presumed to be innocent at the outset of a trial. It is then up to the prosecution to prove that this presumption is false. This relates to the burden of proof. Ordinarily, it is up to the person bringing the case — the prosecution in a criminal trial or the plaintiff in a civil trial — to prove that the conditions specified by the governing legal rule have been satisfied. Sometimes, the burden of proof shifts to the other side. For instance, if a defendant in a criminal trial alleges that they have a defence to the charge, it can be up to them to prove that this is so, depending on the defence.

Legal fact-finding is constrained by exclusionary rules of evidence:Lawyers cannot introduce any and all evidence that might help them to prove their case. There are rules that exclude certain kinds of evidence. For example, many people have heard of the so-called rule against hearsay evidence. It is a subtle exclusionary rule. One witness cannot testify to the truth of what another person may have said. In other words, they can testify to what they may have heard, but they cannot claim or suggest that what they heard was accurate or true. There are many other kinds of exclusionary rule. In a criminal trial, the prosecution cannot, ordinarily, provide evidence regarding someone’s past criminal convictions (bad character evidence), nor can they produce evidence that was in violation of someone’s legal rights (illegally obtained evidence). Historically, many of these rules were strict. More recently, exceptions have been introduced. For example, in Ireland there used to be a very strict rule against the use of unconstitutionally obtained evidence; more recently this rule has been relaxed (or “clarified”) to allow such evidence if it was obtained inadvertently. In addition to all this, there are many formal rules regarding the procurement and handling of forensic evidence (e.g. DNA, fingerprints and blood samples). If those formal rules are breached, then the evidence may be excluded from trial, even if it is relevant. There is often a good policy-reason for these exclusions.

 

Those are some of the key features of legal fact-finding, at least in common law adversarial systems. Collectively, they mean that defending the second premise of a legal argument can be quite a challenge as you not only have to seek the truth but you have to do so in a constrained and, in some sense, unnatural way.