Workers’ compensation insurance laws and requirements for employers vary from state to state, but private employers can generally choose whether to carry workers' compensation insurance coverage. A workers' compensation insurance policy provides lost wages and medical benefits to employees injured on the job—and death benefits for the spouse and dependents (children) of a worker who dies in a work-related accident.

Under workers’ compensation laws in many states employers who subscribe to workers’ compensation insurance receive a significant legal protection—they cannot be sued by an injured employee (or the estate of a deceased employee) unless the employer was grossly negligent (more negligent than simple, ordinary negligence).

In other words, if an employer has workers’ compensation insurance, that is usually the exclusive remedy for an injured employee (known as the exclusive remedy provision in the statute), and the insurance coverage bars an injured employee from suing the employer (known as the workers’ compensation bar).

An employer who does not purchase or subscribe to workers’ compensation insurance is known as a nonsubscriber. Workers’ compensation laws are usually located in a state’s statutes.

In Missouri, workers' compensation insurance is mandatory for most employers. Employers in Missouri are required to carry workers' compensation insurance if they have five or more employees. Construction industry employers, however, must carry the insurance if they have one or more employees. This insurance provides benefits to employees who suffer work-related injuries or illnesses, including medical care, lost wages, and death benefits for dependents of workers who die as a result of their employment. Missouri law provides the exclusive remedy provision, meaning that for employers who have the proper workers' compensation insurance, injured employees typically cannot sue the employer in civil court for damages related to the injury. Instead, they must go through the workers' compensation system. Employers who fail to provide workers' compensation insurance when required to do so can face severe penalties, including fines and the possibility of being sued in civil court by injured employees.