Mployer Liability to Unlawful Acts of Employees

This is a prewrite that I will use as a note on my final exam
The book that has you to use is a?Employment Law for Human Resource Practicea? by David J. Walsh fourth edition.

Tell everything you know about liability (background history, why exist, exceptions, about the law)
If coworker, supplier, worker should have know about the situation makes employer liable
Supervisor who is potentially harassing with NO tangible job action employer not liable( provided that employer has used and given help program and does not take advantage of the program does not hold employer liable. )