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Murder Definition Essay

First Degree Murder Overview

First Degree Murder: Definition

In most states, first-degree murder is defined as an unlawful killing that is both willful and premeditated, meaning that it was committed after planning or "lying in wait" for the victim. For example, Dan comes home to find his wife in bed with Victor. Three days later, Dan waits behind a tree near Victor's front door. When Victor comes out of his house, Dan shoots and kills him.

Most states also adhere to a legal concept known as the "felony murder rule," under which a person commits first-degree murder if any death (even an accidental one) results from the commission of certain violent felonies, such as:

For example, Dan and Connie rob Victor's liquor store, but as they're fleeing, Victor shoots and kills Dan. Under the felony murder rule, Connie can be charged with first-degree murder for Dan's death even though neither of the robbers actually did the killing.

The Elements of First Degree Murder

State laws categorizing murders into first, second and possibly third degrees generally require that first degree murders include three basic elements

  1. Willfulness;
  2. Deliberation; and
  3. Premeditation.

Some states also require "malice aforethought" as an element, though states differ as to how malice must be shown and whether this is a separate requirement from willful, deliberate and premeditated taking of human life. Most states also enumerate certain kinds of killings as first degree murders without need to prove intent, deliberation and premeditation.

Not all states divide murder into degrees. In some places, the top level murder crime is called by another name, such as "capital murder."


In terms of willfulness, first degree murderers must have the specific intent to end a human life. This intent does not necessarily have to correspond to the actual victim. A murder in which the killer intends to kill but kills the wrong person or a random person would still constitute first degree murder. Furthermore, under many state laws, killing through action showing a depraved indifference to human life can qualify as murder in the first degree.

Deliberation and Premeditation

Whether a killer acted with the deliberation and premeditation required for first degree murder can only be determined on a case by case basis. The need for deliberation and premeditation does not mean that the perpetrator must contemplate at length or plan far ahead of the murder. Time enough to form the conscious intent to kill and then act on it after enough time for a reasonable person to second guess the decision typically suffices. While this can happen very quickly, deliberation and premeditation must occur before, and not at the same time as, the act of killing.

"Malice Aforethought"

Under many state laws, perpetrators of first degree murder must have acted with malice or "malice aforethought." Malice generally includes an evil disposition or purpose and an indifference to human life. States treat the concept of "malice" differently. Under some laws, malice aforethought essentially means the same thing as acting with a premeditated intent to kill or extreme indifference to human life. Other states require a showing of malice distinct from the willfulness, deliberation and premeditation generally required for first degree murder.

Enumerated First Degree Murders

State laws often categorize specific types of killings as first degree. In these cases, the typical elements of specific intent to kill, deliberation and premeditation may not be required. These often include:

  • the killing of a child by use of unreasonable force;
  • certain killings committed in a pattern of domestic abuse;
  • the murder of law a law enforcement officer, and
  • homicides occurring in the commission of other crimes such as arson, rape, robbery or other violent crimes.

This list merely illustrates some of the enumerated first degree murders. For a complete list, consult specific state laws.

Many states also categorize certain methods of killing as murder in the first degree. These include intentional poisonings, murders resulting from imprisonment or torture and murders in which the killer "laid in wait" for or ambushed the victim.

Getting Legal Help with Your First Degree Murder Case

In the criminal justice system, first degree murder is one of the most serious charges you could face and it comes with the harshest of penalties. That's why it's important to contact an experienced criminal defense attorney if you've been charged with first degree murder.

Murder is obviously a big issue when it comes to criminal law and you may be asked about it in several guises. For example, you might be asked to identify defences to a murder and discuss issues such as self-defence. Alternatively, you could be asked about the definition of murder and murder’s place within homicide offences.

Definition of murder

Cast your mind back to your earliest criminal law lectures and you may remember a chap called Coke, who provides the classical definition of murder. “Murder is when a man of sound memory and of the age of discretion, unlawfully killeth within any county of the realm any reasonable creature in rerum natura under the King's peace, with malice aforethought”.

Actus reus & mens rea

The actus reus of murder “requires proof that the defendant unlawfully cause the death of the victim within the Queen’s peace”. The mens rea is ‘malice aforethought’ “which is more commonly expressed today as intention to kill or cause GBH”, as established in R v Vickers 1957.

With this in mind, let’s consider a hypothetical case, provided by the lovely folks at Pearson, who published Nicola Monaghan’s Criminal Law (Q&A Revision Guide).

“Five years ago, Gareth’s wife, Sandra, was diagnosed as suffering from a terminal illness. Gareth is devastated at this and becomes extremely distressed while watching his wife’s health deteriorate and seeing her suffer in pain. He decides that he should end her suffering and he kills her.”

Is Gareth criminally liable for the murder of his wife? The actus reus is there insofar that there is no evidence of self-defence, and the victim is a person in being. When applying the tests for causation, factual causation is established because if it were not for Gareth’s actions, Sandra would not have died. With legal causation, Gareth’s actions are the sole cause of death.

However, there is an issue when it comes to the mens rea. It can be argued that Gareth didn’t intend to kill Sandra or cause GBH. Rather, his aim was to end her suffering; there is no direct intention. Unfortunately for Gareth, R v Inglis 2011 established that mercy killings is not a defence to a charge of murder. Additionally, there could have been oblique intention. A person has oblique intent when the event is a virtual certainty of a voluntary act, and they foresee this to be the case. It’s clear that Gareth foresaw Sandra’s death as virtual certainty of his actions and therefore the mens rea is present too.


Coke’s definition ensures that there is a defence to the charge of murder on the grounds of insanity and infancy. Additionally, self-defence is a defence to murder, and in medical cases, double effect is also considered a defence. R v Adams 1957 established this precedent; if death is caused through the administration of lethal drugs such as morphine that is solely intended to remove pain, then this is not murder.

Murder can also be reduced to manslaughter if there is a loss of control, under sections 54 and 55 of the Coroners and Justice Act 2009. Additionally, diminished responsibility is a partial defence. Diminished what?! Allow us to explain.

The Homocide Act 1957 outlines that a person “shall not be convicted of murder if he was suffering from an abnormality of mental functioning” which can arise from a medical condition. It can also be the result of something that impairs a person’s ability to understand the nature of their conduct, to form rational judgement and to exercise self-control. Additionally, it’s manslaughter, not murder, if death is the result of a suicide pact. This is covered under section 4 of the Homocide Act 1957.

That’s that! Obviously there is loads more to discuss on murder, such as its relationship with manslaughter, but we wouldn’t want to tell you everything for the exam, would we?