Bills of attainder are an ancient instrument of tyranny. In England a few centuries back, Parliament would at times enact bills or statutes which declared certain persons attainted and their blood corrupted so that it lost all heritable quality (Ex Parte Garland, 4 Wall. 333, 18 L.Ed. 366 [1867]). In more modern terms, a bill of attainder is essentially a usurpation of judicial power by a legislative body. It envisages and effects the imposition of a penalty — the deprivation of life or liberty or property — not by the ordinary processes of judicial trial, but by legislative fiat. While cast in the form of special legislation, a bill of attainder (or bill of pains and penalties, if it prescribed a penalty other than death) is in intent and effect a penal judgment visited upon an identified person or group of persons (and not upon the general community) without a prior charge or demand, without notice and hearing, without an opportunity to defend, without any of the civilized forms and safeguards of the judicial process as we know it (People v. Ferrer, 48 SCRA 382 [1972]; Cummings and Missouri, 4 Wall. 277, 18 L. Ed. 356 [1867]; U.S. v. Lovett, 328, U.S. 303, 90 L.Ed. 1252 [1945]; U.S. v. Brown, 381 U.S. 437, 14 L.Ed. 2d. 484 [1965]. Such is the archetypal bill of attainder wielded as a means of legislative oppression. x x x⁴⁷

R.A. No. 9335 does not possess the elements of a bill of attainder. It does not seek to inflict punishment without a judicial trial. R.A. No. 9335 merely lays down the grounds for the termination of a BIR or BOC official or employee and provides for the consequences thereof. The democratic processes are still followed and the constitutional rights of the concerned employee are amply protected.

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