under the ISA do not have a right to make representations to an advisory board. They may, within two months from the date of the detention order, make written representations to the Minister. The Minister may, but is not bound to, refer the representations to an advisory board. Any decision on such representations by the Minister is final and cannot be called into question in any court. The burden of proving that a person is a citizen lies on the person claiming to be one, and again the Minister's decision on the matter is final. Extension and suspension of detention The initial order of the Minister for Home Affairs may direct that an individual be detained for up to two years. This may be further extended by directions issued by the President for further periods of up to two years at a time. The Minister is empowered with discretion to suspend a detention order, but also has the authority to revoke the suspension at any time, which reactivates the detention order. Detention orders must be reviewed at least once every 12 months by an advisory board which thereafter makes its recommendation to the Minister. If an advisory board recommends the release of a detainee and the Minister disagrees, the President may exercise personal discretion to order the release. The requirement for regular reviews of detention orders does not apply to detainees who are not citizens. When a detention order is extended, the Minister is not required to provide the detainee with the grounds justifying the extension order or give the detainee an opportunity to appeal against the extension. Scope of judicial review of ISA orders Under administrative law, judicial review is an exercise in which the High Court scrutinizes the executive's decisions and orders to ensure that they conform with the law. If the decisions and orders are not authorized by statute or if they have been made in contravention of administrative law principles, the Court can invalidate them. Similarly, if any exercise of power by an executive body contravenes the Constitution, the Court has a duty to declare it invalid. With regards to the ISA and the powers to detain without trial, the scope of judicial review was subject to a succession of changes between 1988 and 1990. These changes revolved around the issue of whether the discretion of the President and the Home Affairs Minister should be assessed