A central implication of our theory of law lies in the concept of legal responsibility.  as we saw, law was the setting up of a retributive institution of punishment.  Our formula for that institution (P=HxR) requires that we can only punish when the person committing the crime is responsible.  The notion of responsibility is quite close to that in morality but there are differences that we should note.  There are many different senses of the English word "responsible" that need to be distinguished for this purpose.

• A) Role responsibility or a duty of our role: Someone is responsible for getting lights.
• B) Evaluation of a person: Means he is reasonable or reliable, that he regularly does his duty. This is something like capacity responsibility.
• C) Necessary condition for blaming, praising, or punishing someone.  In law we sometimes use 'liability' and 'cul­pability' to be precise about this sense.

Where 'liability' typically concerns civil harms and lawsuits, criminal law may talk more about culpability which is vaguely equivalent to morally responsible--but again with deviations. Intent is important in both, but in law, it is frequently not actual intent but rationally construed intent.  That is we do not have to prove an internal subjective state was present, but see if the criminal act was part of a pattern of actions that rationally (normally) fits with an intent.  This feature of law derives from the importance of attributing rationality to humans in justifying the law, hence the possibility of coherent planning and governing behavior by some concept or rule. We saw similar assumptions in the adjudicative practice of rationally construing the intent of a law and the Basic Law.)

Normally there are three criteria for responsibility:

1. Mental or mens rea (guilty mind) requirement: One must have the capacity to understand, and control his conduct.
2. Some kind of causal connection to the harm done – actus reus (guilty act).
3. Or there must be some other responsibility relation to the cause of the harm: e.g., a servant, one's dog, or negligence.

Causation

Causation creates a number of philosophical problems for an account of legal and moral responsibility and we will deal only sporadically with determinism and the privacy of the mental.  An important point that law and morality share is that causation carries a limit in a responsibility judgment. The limit is a interesting one from our point of view since we have justified law based on predictability, and the right of rational or free people to rule by clear forewarning.  But there are limits to our ability to predict and these figure crucially in the Legal notion of causal responsibility.

The philosophical discussion of cause has changed from the early days of the law in Europe.  We used to think of causes as powers and chains of transmission.  Most theorists have now given up talk of causation in favor of talk of law‑like explanation and prediction.  Notice that is what is really important to the normative perspective of the law.  Still, most ordinary events are far from predictable.  There are often infinite chains of events, laws and circumstances.  The chain of causation for any event goes all the way back and spreads quickly throughout the universe.

Think of a complex chain of causes leading to an event.  Causation, for purposes of legal and moral blame, occurs when a responsible agent intervenes in that chain. However, not all kinds of intervention are relevant to causal responsibility.  Two exceptions to causal intervention are particularly important:

1. When the causal intervention had unpredictable results:  The knowledge requirement of moral respon­sibility is presumptive in law.  If the person could reasonably have predicted the causal outcome, he cannot be responsible for it. If the result and the risk is unpredic­table, the person is not causally responsible.
2. When the voluntary act of another rational agent intervenes:  If one of my acts causes the harm, but the chain crucially involves some other per­son's f­­­­ree and independent later act, then I am neither culpable nor l­­­iable.  (The intervening agent must not be my dupe, servant, agent etc.)

Real causal chains don't end but responsibility chains do.  This limitation is independent of intent.  If someone made voodoo doll intending thereby to kill someone and the doll actually does cause death by some natural but unpredictable chain of events, the doll maker would still not be causally responsible. 

The second condition reflects some important Kantian moral insights. I am not responsible for someone's criminal behavior even if I justified it (anger, resentment etc.)  No matter what the provocation, rational agents presumptively have the capacity to choose their response.  Consider whether or not a Doctor should tell a depressed patient that her cancer is still growing and will kill her in 2 months.  A Kantian conscience says our duty to tell the truth is not changed by the behavior of the person hearing it.  That is her choice and in respect of her moral dignity owe her the right to make the choice.  Many moral puzzle cases turn on this difficult issue.  Should one have killed Hitler when he was a child? If someone says "if you don't kill one of these 5 hostages, I will kill you and all of them, what do you do? Legally you shouldn't kill and it's up to Hitler and the terrorist to choose their own actions.

These doctrines get put under pressure by possible police tactics.  If the police recruit you to do a crime, then although you may have done wrong, their behavior is probably worse and it is called entrapment.  That is an inappropriate method of enforcement.  The person convicted might never have planned or started a criminal project without that inducement. 

Negligence

Another area of the law that reflects the assumptions and normative theory justifying the law is the law of tort--the standard lawsuit.  The key concept in the law of tort is negligence. This is another area where the law comes into our daily decisions in important ways. We should know the difference between negligence and recklessness in law.

The mens rea component of legal liability has a series of gradations.

1. Our mental state may be such that a harm is intentional, that is, we plan and carry out a plan to get that result.  This is the strongest form of mens rea (first degree murder).  Other regularly used terms for this mental state is voluntary or deliberate.
2. The second gradation is one where we know what the outcome of our actions but don't intend or actually want that outcome.  We usually are in this mental state when the outcome is the least of two evils.  Most of the discussion of this kind of mens rea deals with abortion and moral puzzle cases.  In Catholic Church law and moral theory there has been a lot of discussion of the doctrine of double effect to deal with the doctor who performs an abortion to save the life of the mother.  He knows, but does not intend, the consequence--the death of the fetus.  Similarly in the puzzle cases where you have to choose to steer the train where it will kill one person of five people.  There is no special legal term (that I know of) for this kind of mens rea.  I suppose an example would be justifiable homicide (self or other defense).
3. The third level is recklessness.  This is a case where you don't know that you will do some harm but know that your action creates a risk of some harm.  And you still act in willful disregard of that risk.  Reckless driving, weaving, speeding, driving while intoxicated, and so forth are examples of this kind mens rea.  Manslaughter is a typical conviction for when such an action results in someone's death.
4. The fourth level is negligence.  Here you don't willfully run a risk that you knew existed, but negligently (irresponsibly, carelessly) run a risk you should have known was there.  You may never have thought about it, but you should have!  A typical case is a builder who leaves a pile of bricks on a scaffold while building a house where a lot of people walk.  If one falls off and hurts someone he may insist that the risk had never occurred to him.  The law's answer is that it should have.  You are responsible to see that such things occur to you. 

Why is that?  It uses what is called the "reasonable man" rule.

Reasonable Man Rule

What would a reasonable man with ordinary capacities have done in that circumstance?  In other words, negligence brings us back to the assumptions that justify the rule of law.  We are capable of rationally projecting and making plans and envisioning consequences.  Our legal responsibilities are drawn against the assumption of that basic capacity.

The standard is complicated a little by considerations of our professional role.  So it is not merely the standard average man's capacity to predict consequence when we decide if a medical doctor was negligent.  There the responsibility is relative to the standards of the profession.  It is also relative to the level of general and professional knowledge.  Our liability changes as we learn more things, say about aids.  What counts as an unreasonable risk depends on what is known about how the disease is spread etc.

This is an aspect of capacity responsibility. The essential question to answer is could the defendant have known or done something to prevent the harm?  It is not actual her actual state of mind, but objective standards of care and capacity responsibility that are at issue.

Reasonable person standard is central to many legal issues.  Law is made for rational, planning, projecting, predicting etc. beings.  Many aspects presuppose a standard ability to do this and expects us to exercise that capacity.  Another example is ignorance of the law.  It is not an excuse in law because we could have known and a normal rational adult would have known. 

Risk Rule

The crucial aspect of negligence is the risk created that should have been appreciated by normal standards.  The liability is limited to aspects of risk created by negligence. The example with which Keeton starts illustrates this.  If you place poison on a shelf in a restaurant, you create a negligent risk.  Poison in a food preparation area might cause harm to someone by mistaken use as an ingredient.  Now suppose the box explodes from the heat in the kitchen. The risk that is rationally predictable is the poisoning risk, not the exploding risk. A negligent actor is legally responsible for that harm and only that harm, of which the negligence is a cause in fact.

A similar case would be a truck loaded with explosives and no warning sign runs over someone.  The truck caused a harm, but the lack of warning did not create the risk of running over someone.  It did allow the truck to start out earlier and if it had been a minute later the accident would not have happened.  So the conduct was a cause in fact, but not linked to the rationally predictable risk.  This is another case where we limit causation to the considerations  that could have been predicted, are significant and do not involve an independent and unpredictable conjunction of events.

The negligence rule, like insanity rule we will discuss next, has undergone several versions trying to get the implicit principle formulated correctly.  The simple formulation is that negligence is a cause in fact of the harm.  That allows some ambiguity--the negligence in placing the poison there was a cause in fact of the explosion harm. A less ambiguous formulation to deal with that is that the negligent aspect of the conduct is a cause in fact.    But it may be difficult to sort out aspects of conduct.  The third formulation focuses on the set of harms that are negligently risked.  Then if the actual harm brought about by the conduct falls in this set the actor is liable by reason of negligence for damages.