The tragic reality in America today is that mass shootings happen far too frequently. They can occur in schools, workplaces, retail stores, restaurants, public buildings, public transportation, outdoor concerts, and anywhere else. Other than the shooter, the question of who may be liable when these events occur is one that courts are grappling with currently. In many cases, a school or business cannot be held responsible for the criminal actions of another person, because they generally cannot predict and prevent a shooting before it happens. However, when, for example, a school is aware of red flags from a student and keeps them in class or a business receives threats but fails to implement basic security measures, there may be liability for failing to properly respond to the known risk. A business that sells a gun to the shooter might also be held liable if they knew the shooter’s plans, failed to conduct a background check, or sold to a minor. Gun manufacturers are generally immune from lawsuits, but may be liable for irresponsible marketing or creating a public nuisance.