Universities discuss this all the time. It's incredibly hard to prove.
This is one reason we keep exams -- while they have many problems (particularly in Computer Science), forcing someone to sit in a room and answer questions gives a way of checking the student really does understand the course.
This is one reason we keep exams -- while they have many problems (particularly in Computer Science), forcing someone to sit in a room and answer questions gives a way of checking the student really does understand the course.