A school district performs standard teacher evaluations including unannounced visits to classrooms, and messages are often delivered to the classroom throughout the day. It is discovered that a teacher engaged in intimate sexual contact with a student during the school day. Is the school district liable for negligent hiring? Should the employer have known that this could happen? [P. L. v. Aubert, 545 N.W.2d 666 (Minn. 1996).]