There are a variety of conditions that will tend to negate elements of a crime, known as defenses. In many jurisdictions, the entire burden to prove a crime is on the government, which also must prove the absence of these defenses, where implicated. Defenses may provide partial or total refuge from punishment.
Contractual defenses include the following: (1)failure of consideration, (2) alleged obligation not within scope of contract, (3) full or substantial performance rendered, (4) illegal purpose, (5) suspension or termination of performance justified because of client's breach, and (6) failure of a condition precedent.
Defenses to negligence include the following: (1) The Alleged duty was not owed; (2) the accountant did not breach the duty because (s)he exercised reasonable care; (3) the plaintiff did not suffer a loss; (4) the accountant's behavior was not the cause of the party's loss, for example because it was caused by the party's own negligence or fault or by a third party; (5) the plaintiff is not within a class of parties to whom an accountant is potentially liable under the applicable state law; (6) the person alleging harm assumed the risk, e.g., by accepting a contract containing an effective disclaimer; and (7) the statute of limitations has expired.
If you are unconscious while you commit a crime, California law excuses your actions.26 This legal defense is applicable to people who, for example, commit criminal acts while sleeping, delirious, suffering from an epileptic seizure, or who are involuntarily intoxicated.
Assumption of the Risk: Common law developed a doctrine in which the defendant will win if the defendant can prove that the plaintiff voluntarily assumed a known risk. For example, have you ever examined cigarette packages? They bear various warnings, some of which are "Surgeon General's Warning: Smoking by pregnant women may result in fetal injury, premature birth, and low birth weight,"...
Necessity: Whenever a person enters another's land for self-protection, the law recognizes that as a necessity and disallows the nominal damages ordinarily awarded for trespass. For example, if you are in a boat on a lake and a storm suddenly develops, you may enter a private cove, tie up to a private dock, and find shelter on the land in order to protect yourself.
Mistaken eyewitness identification is the leading cause of wrongful conviction. It can happen because:
you (your physical description, your clothes, your car, etc.) happen resemble the actual perpetrator, someone assumes you are to blame for a criminal act (for example, an elder’s doctor reports you for violating Penal Code 368 PC, California’s elder abuse law18 because he sees bruises and incorrectly assumes you, the primary caretaker, must have inflicted them), or someone points the finger at you to cover-up his/her own criminal liability.
Self-defense is a defense commonly asserted by someone charged with a crime of violence, such as battery (striking someone), assault with a deadly weapon, or murder. The defendant admits that he or she did in fact commit the crime, but claims that it was justified by the other person's threatening actions.
Truth: truth is one of the best defenses for the tort of defamation. A defendant will win if the defendant can prove that the statement was true.
The prosecutor must convince a judge or jury of a defendants guilt "beyond a reasonable doubt." This heavy burden of proof in criminal cases means that judges and jurors are supposed to resolve all reasonable doubts about the defendants guilt in favor of the defendant. With such a high standard imposed on the prosecutor, a defendant's most common defense is to argue that reasonable doubt of guilt exists.
Defense attorneys can use many different arguments to protect the defendant's rights and to make the prosecution prove its case. It is important that the defense attorney raise the various defenses at the proper time. A defense attorney can discuss available defenses before any charges are brought, which could lead to the prosecution to pursue lesser charges or to not even bring any charges at all.
Defenses can be raised at several points on the timeline of a case. Some defenses may be presented to the grand jury, some are presented at pre-trial and others aren't raised until the trial itself. The time to raise a defense is a strategic matter and can have a significant impact on the outcome of a case.