Don't let students participate in graduation defense? What does this mean? That is, students want to take part in graduation defense, and the teacher won't let you do so, so you have to take part in graduation defense? This right is definitely not available. If you don't want to take part in your graduation defense, you don't submit it, or you hide in time. What can your thesis advisor do? Even if he ties you up and takes you to the National Defense Commission, he can't pry your mouth open without saying a word, can he? Even if he can pry your mouth open, he can't catch your vocal cords if you don't make a sound, can he?

What if you mean that college students want to take part in the graduation thesis defense, but the teacher won't let them? This right is there. Your thesis is written in a mess. If your tutor can't pass this test, he won't let you take part in the defense.