The constitutional principle of legality of taxation requires that any tax with all of its essential elements must have a firm basis in law. That clearly means no tax can be levied except under authority of a law. As fundamental rights and personal freedom cannot be restricted except by law and as any act of the administration, including any administrative act of tax assessment and collection requires a firm basis in law. Also the essential elements of a tax must be provided in an enabling law. Such elements like taxpayer, taxable event, object of taxation, tax base, tax rates, and tax exemptions, which must be explicitly included in a tax law, are called as the basic concepts of taxation.