Section 4. Organizational Structure. — The Department shall consist of the following constituent units:

1. Department Proper;

2. Office of the Government Corporate Counsel;

3. National Bureau of Investigation;

4. Public Attorney's Office (as an attached agency);

5. Board of Pardons and Parole;

6. Parole and Probation Administration;

7. Bureau of Corrections;

8. Land Registration Authority;

9. Bureau of Immigration; and

10. Commission on the Settlement of Land Problems.