PRINCIPLES OF CRIMINAL LIABILITY
"Law, with all its weaknesses, is all that stands between civilization and barbarism" (John Derbyshire)

    Criminal liability is what unlocks the logical structure of the criminal law. Each element of a crime that the prosecutor needs to prove (beyond a reasonable doubt) involves a principle of criminal liability. There are some crimes that only involve a subset of the principles of liability, but these are rare and are called "crimes of criminal conduct." Burglary, for example, is such a crime because all you need to prove beyond a reasonable doubt is an actus reus concurring with a mens rea. On the other hand, there are crimes that involve all the principles of liability, and these are called "true crimes" that reflect "black letter law." Homicide, for example, is such a crime because you need to prove actus reus, mens rea, concurrence, causation, and harm. The requirement that the prosecutor must prove each element of criminal liability beyond a reasonable doubt is called the "corpus delicti rule."

Liability needs to be distinguished from the following concepts:

    In general, liability is one of the most important concepts in law.  From the above list, it is closest to responsibility, but more strictly refers to the idea of "legal responsibility" as in the notion from civil law where a person is "legally liable" if they do not meet some "legal responsibility."  Some good synonyms for it are answerability or accountability.  Liability is inherently a social concept, which implies not only some harm is done to society, but there is some collective accountability involved.  Of course, pure collective accountability is called "vicarious liability" but modern societies (and even Anglo-American common law) have moved away from collective or community-based systems of responsibility to systems where governments get to declare what is criminal or quasi-criminal.      

There are five principles of liability in criminal law:

THE PRINCIPLE OF ACTUS REUS

THE PRINCIPLE OF MENS REA

THE PRINCIPLE OF CONCURRENCE

THE PRINCIPLE OF CAUSATION

THE PRINCIPLE OF RESULTING HARM

    Harm is the objective, material substance of the crime, as distinct from the subjective component of mens rea.  The basic principle is that no conduct can truly be called a crime unless it causes some resulting harm.  Such conduct must be injurious to the public at large or injurious enough to any individual that society takes notice of it and regards it as a harm against itself.  In other words, there must be some "material unlawfulness." There is also an assumption that resulting harm is done by challenging the legality of the law itself. 

RESPONSIBILITY FOR CRIME: PRESUMPTIONS

    Presumptions are court-ordered assumptions that the jury must take as true unless rebutted by evidence. Their purpose is to simplify and expedite the trial process. The judge, for example at some point in testimony, may remind the jury that it is OK to assume that all people form some kind of intent before or during their behavior. It is wrong, however, for the judge to order the jury to assume intent or a specific kind of intent in a case. Presumptions are not a substitute for evidence. Presumptions are supposed to be friendly reminders about safe, scientific assumptions about human nature or human behavior in general. The most common presumptions are:

    It is important to understand that presumptions are not inferences. Presumptions must be accepted as true by the jury. Inferences may be accepted as true by the jury, but the trick is to get the jury to believe they thought of it first. Lawyers are not allowed to engage in the practice of "stacking of inferences", or basing an inference solely upon another inference. Lawyers are also prohibited by logic from making certain "impermissible inferences" and here's an example of how the logic goes:

Evidence admitted:

Inferences that can be drawn:

Witnesses testify that X repeatedly hit Y on the head with a club until stopped by passerbys Intent to kill or seriously injure; Purposely or Knowingly using club as deadly weapon.
Witnesses testify that X repeatedly hit Y on the head with a rolled-up newspaper Intent to kill cannot be inferred; newspaper cannot be construed as a deadly weapon

INTERNET RESOURCES
Anatomy of a Prosecution
Buffalo Criminal Law Review
The General Principles of Liability (pdf)

PRINTED RESOURCES
Fletcher, G. (1996). Basic Concepts of Legal Thought. NY: Oxford Univ. Press.
Gardner, T. & T. Anderson. (1996). Criminal Law: Principles and Cases. 6th ed. Minneapolis: West Publishing

Posner, R. (2004). Frontiers of Legal Theory. Cambridge, MA: Harvard Univ. Press.
Samaha, J. (1999). Criminal Law. 6th ed. Belmont, CA: West/Wadsworth.

Last updated: Dec 18, 2012
Not an official webpage of APSU, copyright restrictions apply, see Megalinks in Criminal Justice
O'Connor, T.  (2012). "Principles of Criminal Liability," MegaLinks in Criminal Justice. Retrieved from http://www.drtomoconnor.com/3010/3010lect02.htm.