It's not the criminal defendant's job to prove their innocence; it's the prosecutor's job to prove the defendant's guilt. But that doesn't mean the defense must sit silent during the case. An experienced criminal defense attorney holds many tools to use as potential defenses during the pendency of a criminal action, from poking holes in the prosecution's case to raising defenses specific to the defendant's conduct or case.
During trial, the prosecutor must prove the defendant's guilt of the charges beyond a reasonable doubt. If the prosecution fails to meet this burden, the jury (or judge) must acquit the defendant. Defendants don't need to prove their innocence. Still, they have the right to defend themselves by attacking the prosecution's case and trying to raise reasonable doubt. Even if the prosecution succeeds, the defense might be able to raise defenses showing that the case should be thrown out or the defendant's conduct was justified or excused. Although many potential trial defenses exist, below are some of the most well-known and commonly used defenses. The success of any defense is, and always will be, case dependent.
As discussed above, the prosecutor has the burden to prove the defendant guilty beyond a reasonable doubt. This is the highest burden of proof in the legal system, and it applies to each element of the crime. To raise reasonable doubt in the minds of the jurors, defense attorneys try to poke holes in the prosecution's case by attacking the evidence and credibility of their witnesses.
Witness testimony. To undermine witness testimony, the defense might try to show the witness was biased against the defendant or motivated to lie. Perhaps, the witness is a co-defendant who cut a deal with the prosecutor, agreeing to testify against the defendant in order to receive a reduced sentence. The defense could also point out inconsistencies or implausible circumstances in a witness's story. An eye witness's limited opportunity to see the crime could be used to the defense's advantage as well.
Evidence. Attempting to discredit the evidence can also hurt the government's case. Defendants do this in several ways. If the defendant claims to be innocent, the defense might try to introduce evidence showing someone else committed the crime. Or the defendant might present an alibi, a claim that the defendant was elsewhere at the time of the crime and couldn't have done it. Emphasizing the fact that no physical evidence exists can also raise doubt in the minds of the jurors. Although the prosecution doesn't need physical evidence to prove its case, juries often like to see something other than circumstantial evidence. If a witness sees an individual with a gun running from a murder scene, you have circumstantial evidence of the runner committing the crime. If, on the other hand, the runner's DNA was found on the dead body, you have as physical evidence. Finally, the defense team could scrutinize and call out faulty or suspect police methods used in gathering or handling the evidence.
Often when a defendant is charged with a violent crime, such as murder or battery, the defense will be one of self-defense. In this situation, the defendant admits to the act but argues it was necessary to defend themselves from the initial aggressor (the injured or dead victim). Defendants can raise a similar defense when they defend an innocent victim from harm. For example, say a man sees someone attacking a woman in an alleyway. The man steps in to help the woman but ultimately severely maims the attacker. If the prosecutor charges the man with assault, he'd likely contend the injury happened in his pursuit of trying to save the woman. Generally, a person claiming defense of self or another must have acted out of a reasonable belief of immediate harm and with a reasonable amount of force.
With the insanity defense, a defendant claims not to be culpable for the crime based on the inability, at the time of the crime, to understand their actions or discern right from wrong. To prove legal insanity, both sides bring in experts, such as doctors or psychiatrists. A defendant found not guilty by reason of insanity rarely walks away scot-free. Rather, the outcome usually entails the defendant sentenced to a state-run institution for treatment. Some defendants shy away from using this defense because the time confined to a psychiatric facility could be longer than a prison sentence. Although it's a well-known defense, the insanity defense is controversial and uncommon in practice.
Voluntary intoxication is not a defense to most crimes. The law allows for a few exceptions, however, and those exceptions are known as specific-intent crimes. Specific-intent crimes require that the defendant be able to form the criminal intent necessary to commit the crime. For example, burglary requires an individual to illegally enter a building with the intent to commit a crime inside. If, due to extreme intoxication, the defendant cannot possibly form the intent to commit a crime, the defense might argue intoxication negates the mental state required to convict. Even if successful, the defense might hear a "not guilty" on the burglary charges but a "guilty" on other charges, such as trespassing, disorderly conduct, or criminal damage to property.
The defense of duress or coercion generally involves the defendant admitting to the commission of the crime. Although they engaged in misconduct, the defendant only did so under extreme duress, such as someone holding a gun to their head and ordering them to steal a vehicle. This defense usually has several requirements, which vary by jurisdiction. These conditions can include that the threat of harm be inescapable and immediate and the type of harm be serious bodily harm or even death. The threatened harm could also be directed at a defendant's family member.
While it might not be the first defense one thinks of, the statute of limitations is an important defense. Once a crime occurs, the prosecutor must file charges before a cutoff point set in the law—referred to as the statute of limitations. The time limit to file charges varies depending on the jurisdiction, the crime, and the circumstances. Suppose the limitations period for theft is five years. If the prosecutor files theft charges six years after the crime, the defendant can ask the court to dismiss the case. Unless the prosecutor can show an exception existed (for instance, the theft continued for two more years), the judge must dismiss the case. In many jurisdictions, the defendant must raise the statute of limitations issue at the trial level or lose the defense.
If you have been arrested for or charged with a crime, contact a criminal defense attorney today. One or more of these potential defenses might be applicable to your case and timing is of the essence. In some jurisdictions, the law specifies that the defense must inform the prosecution of certain defenses well in advance of the trial date.