In general, the broadest liability is imposed on the master in the case of tortious physical conduct by a servant, as discussed in Relationships between Principal and Agent . If the servant acted within the scope of his employment—that is, if the servant’s wrongful conduct occurred while performing his job—the master will be liable to the victim for damages unless, as we have seen, the victim was another employee, in which event the workers’ compensation system will be invoked. Vicarious tort liability is primarily a function of the employment relationship and not agency status.
Ordinarily, an individual or a company is not vicariously liable for the tortious acts of independent contractors. The plumber who rushes to a client’s house to repair a leak and causes a traffic accident does not subject the homeowner to liability. But there are exceptions to the rule. Generally, these exceptions fall into a category of duties that the law deems nondelegable. In some situations, one person is obligated to provide protection to or care for another. The failure to do so results in liability whether or not the harm befell the other because of an independent contractor’s wrongdoing. Thus a homeowner has a duty to ensure that physical conditions in and around the home are not unreasonably dangerous. If the owner hires an independent contracting firm to dig a sewer line and the contractor negligently fails to guard passersby against the danger of falling into an open trench, the homeowner is liable because the duty of care in this instance cannot be delegated. (The contractor is, of course, liable to the homeowner for any damages paid to an injured passerby.)