Dissertation Defense procedures are described in the Graduate College policies regarding Doctor of Philosophy Program Requirements.
The student must be a Ph.D. candidate at least for one year before he/she can defend his/her doctoral thesis.
Note that it is required that the appointment and scheduling of the dissertation defense (Form D-4: Final Oral Defense Committee Appointment and Schedule) must be filed in the Graduate College at least 4 weeks prior to the scheduled date of the examination.