See - 212140-41.pdf
"x x x.
The rights to due process in administrative cases as prescribed in Ang Tibay, as amplified in GSIS, are granted by the Constitution; hence, these rights cannot be taken away by mere legislation. On the other hand, as repeatedly reiterated by this Court, the right to a preliminary investigation is merely a statutory right,32 not part of the “fundamental and essential requirements” of due process as prescribed in Ang Tibay and amplified in GSIS. Thus, a preliminary investigation can be taken away by legislation. The constitutional right of an accused to confront the witnesses against him does not apply in preliminary investigations; nor will the absence of a preliminary investigation be an infringement of his right to confront the witnesses against him.33 A preliminary investigation may be done away with entirely without infringing the constitutional right of an accused under the due process clause to a fair trial.34
x x x."
