Criminal Law

IX. Model Penal Code and Mental States

The Model Penal Code (MPC) is a set of principles that many states rely upon when drafting criminal statutes. The MPC covers four types of mental states:

  1. Purposely: You intend the actual result. For example, when you buy a gun, load the weapon, wait in the parking lot for your victim, hide in the bushes when you see him approach, and then leap out and discharge your weapon into the other person, there can be little doubt that you have purposely taken the life of another.
  2. Knowingly: Perhaps you didn’t want to hurt anyone, but you did. For example, you might keep a gun in your desk for self-defense. Then your coworker tells jokes at your expense and insults you in front of others. Angry, you shoot him dead. Maybe you didn’t plot and scheme to kill your coworker, but you knowingly took the life of another because everyone knows that if you shoot a person with a gun, the person can die.
  3. Recklessly: You are actually aware that you were involved in an activity that created a substantial and unjustified risk, but you ignored the risk and the likely outcome. For example, if you decide to street race another car and reach speeds of 70 miles per hour on a residential street, and an 80-year-old lady walking home from church steps off the curb to cross the street and you strike and kill her, you have recklessly taken the life of another.
  4. Negligently: You should be aware that a substantial and unjustified risk is created by your conduct. For example, if it is nighttime and you fail to turn on your headlights and a 10-year-old boy riding his bicycle is playing in the street and you strike and kill him with your car, you have negligently taken the life of another because driving without headlights creates a substantial and unjustifiable risk to bicyclists or pedestrians.

X. Causation and Concurrence

For crimes that result in a harm to someone, the state must prove that the act or omission of the accused was the ordinary and probable cause of the resulting harm. In cases where the harm is direct and immediate, determining that the defendant was the cause of the harm is not difficult. For example, when Barney hits Betty on the head with a baseball bat and she dies from a massive brain hemorrhage, causation is not an issue. However, when there is a chain of events that eventually leads to death, causation is more difficult for the state to prove. In those instances, the prosecutor must show that the defendant was both the cause-in-fact and proximate cause of the death. Typically, courts will first ascertain whether the actions were the cause-in-fact of the injury. This is sometimes called the “but-for” test (Dix, 1993). For example, if Fred cuts the brake line on Barney’s car and Barney crashes and dies, Barney would not have been killed “but for” the act of cutting the brake line by Fred.

After the accused is shown to be the cause-in-fact of the harm, the state must also prove that the defendant’s act was the proximate cause of the resulting harm. Determining this is often made difficult by the occurrence of intervening causes (Beale, 2002). For example, using the previous example, would it be fair to charge Fred with murder when Barney was only slightly harmed in the accident and was taken to the hospital where he dies after waiting for a physician for 16 hours in the emergency room?

Determining proximate cause depends upon the factual situation of each case. It must be determined whether the intervening cause was a dependent intervening cause or an independent intervening cause. A dependent intervening cause is foreseeable and does not relieve the defendant of liability. For example, if Barney stabs Fred and a doctor is negligent in treating Fred at Bedrock Hospital, it was foreseeable that a victim might die from subpar treatment. An independent intervening cause gives the opposite result, relieving the defendant of criminal culpability. Using the example above, if Fred is operated upon by an intoxicated doctor who slices through an artery and is so drunk that he can’t even attempt to stop the bleeding, this is not foreseeable and the chain of causation between the defendant and the result is broken. Again, the key is forseeability (Katz, 2002).

Equally important is the union of the act and the intent. Thinking about committing a criminal act is not a crime. A person might fantasize about robbing a bank or killing a spouse, but if the individual does nothing to act upon these thoughts, the person is guilty of nothing. Moreover, if someone accidentally gives her spouse the wrong medicine or picks up the wrong money bag at the bank, the person has done an act that caused harm, but she had no mens rea or evil intent. There must be a joint operation of act and intent that results in the social harm (Beale, 2002).

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