Who is the Victim?

I have been robbed a few times but the one time I was robbed where I was not the only victim was when I was teaching High School in Thunder Bay. I was teaching a senior Mathematics class and it was the day before the big test at the end of a unit of study. I had just learned that some of my students would be gone the next day so they had requested that they write the test early. I had a file with the tests on my desk and the students were studying, working in groups, working at the black board and asking questions as they prepared for the test. At the end of the class one student dropped a note on my desk which told me to check the test file as one of the students had taken a test from the file. The next day I confronted the class telling them that one of the test was missing and I needed to know who took it. After several days in which the student services and the administration was involved one the students came to me and told me that she had taken the test. The administration had already made the decision that she would receive a 0% for that test. As I talked to her she had not realized that what she had done would hurt anyone. However, the student who had left me the note told me later that he had done that because he felt that she was getting an unfair advantage over the other students and they were competing for placement in University. He also told me that though this student was a good friend of his he felt that what she had done had both hurt the class and had hurt me. He said it was wrong for her to do that to him, the others and to me. I had great respect for the student who came forward to make known the incident. Who was the victim and who suffered for the crime?