Tort principles can be viewed along different dimensions. One is the fault dimension. Like criminal law, tort law requires a wrongful act by a defendant for the plaintiff to recover. Unlike criminal law, however, there need not be a specific intent. Since tort law focuses on injury to the plaintiff, it is less concerned than criminal law about the reasons for the defendant’s actions. An innocent act or a relatively innocent one may still provide the basis for liability. Nevertheless, tort law—except for strict liability—relies on standards of fault, or blameworthiness.
The most obvious standard is willful conduct. If the defendant (often called the tortfeasor—i.e., the one committing the tort) intentionally injures another, there is little argument about tort liability. Thus all crimes resulting in injury to a person or property (murder, assault, arson, etc.) are also torts, and the plaintiff may bring a separate lawsuit to recover damages for injuries to his person, family, or property.
Most tort suits do not rely on intentional fault. They are based, rather, on negligent conduct that in the circumstances is careless or poses unreasonable risks of causing damage. Most automobile accident and medical malpractice suits are examples of negligence suits.
The fault dimension is a continuum. At one end is the deliberate desire to do injury. The middle ground is occupied by careless conduct. At the other end is conduct that most would consider entirely blameless, in the moral sense. The defendant may have observed all possible precautions and yet still be held liable. This is called strict liability. An example is that incurred by the manufacturer of a defective product that is placed on the market despite all possible precautions, including quality-control inspection. In many states, if the product causes injury, the manufacturer will be held liable.