Note: These are just ideas, you are free to choose any idea as long as it passes muster with your professor. Also, some of these topics may not cover enough ground--some may be too broad.
Intermediate Sanctions
ISP
Boot Camps
Halfway Houses
EM/Home Confinement
Probation Effectiveness, Predictors of Success/Failure
Parole, "Re-entry" Issues
Restorative Justice/Community Justice
Prisons
Violence
Prison Rape
Crowding
Gangs/STGs
Subculture/Inmate Social System
Female Prisons/Culture
Inmate Rights/Corrections Law
Management
Corrections Officers (burnout, use of force, sources of power, etc.)