HR pros have no shortage of scary stories. As Halloween approaches, we're revisiting some of the most nightmare-inducing headlines of 2021.

Most touch on compliance, and employers often are told that prevention is the best defense to these types of issues. And a major component of that prevention is training for supervisors, as experts say managers are the most common cause of employment law violations.

Here are 10 stories that are sure to keep you up night, and provide fodder for next year's compliance training.