Murder charge defenses fall into two categories: assertions that the defendant did not commit the offense, and admissions that the person did commit the crime without meeting the requirements for first-degree murder charges. In some cases, defendants can argue that the prosecution has not proven the elements of a first-degree charge, and the prosecutor has the burden of proof. Defendants should call an attorney experienced in state criminal law.
In a first-degree murder case, a defendant can argue mistaken identity, or that the prosecutor has filed charges against the wrong person. Other possible arguments include challenges to the prosecution’s assertions that the defendant was at the crime scene. This defense can provide evidence implicating someone else, but the court does not require such proof.
Not every homicide is a crime, let alone a first-degree murder. A common justification for a homicide is self-defense or defense of other people. For a successful self-defense claim, the defendant’s attorney must demonstrate that the killing resulted from the use of force against the fear of bodily harm or death. The proportional and reasonable defense of other people justifies some homicides, and the force must be reasonable to the threat faced by the defendant.
Fulfilling a Duty
Some killings by public and law enforcement officers are ruled justifiable homicides. If a police officer kills a person in the line of duty without negligence, recklessness or illicit intent, the killing does not meet the legal definition of murder.
Misfortune or Accident
Killings committed accidentally and in the course of a lawful activity are not considered murder. Some killings may result in manslaughter liability, but are not covered by first-degree murder laws unless they take place during the commission of an offense. In some cases the use of force beyond the norm can turn a killing from an accident into a murder.
The Insanity Defense
Most jurisdictions allow the insanity defense to be used in first-degree murder cases. However, every location treats it differently. In most cases, insanity is defined as a cognitive inability to appreciate the severity of the offense, or an inability to recognize that the act is morally wrong. Some areas add a volitional component to the insanity defense, which covers those with impulse control issues.