In general, workers’ compensation policies cover most, but not all, on-the-job injuries – even when an injury is caused by employer or employee carelessness. However, injuries that happen because an employee is intoxicated or using illegal drugs are most likely not covered. Other examples of injuries that may not be covered are injuries suffered when an employee was not on the job or injuries suffered when an employee’s conduct violated company policy. The rules vary widely state by state, and rules can be changed from time to time.