Lord Diplock (delivering the judgment of the Board):

On 13 January 1976, in Georgetown, Penang, the appellant Teh Cheng Poh was found in possession of a revolver and ammunition. This happened in the course of a search by a police patrol which had been instituted as a result of an emergency phone call complaining of an armed robbery. The appellant was subsequently charged with two offences under s. 57(1) of the Internal Security Act. 1960. One was of having in his possession in a security area without lawful excuse a firearm without lawful authority therefor; the other charged a similar offence in respect of the ammunition. The mandatory penalty for these offences is death.

Penang, in common with all other areas in Malaysia, had been declared to be a security area for the purposes of Pt II of the Internal Security Act, by a Proclamation of HM the Yang di-Pertuan Agong made on 15 May 1969 ("the

Security Area Proclamation"). If this Proclamation were still effective on 13 January 1976 the offences with which the appellant was charged would constitute "security offences" within the meaning of the Essential (Security Cases) (Amendment) Regulations, 1975 ("the Security Cases Regulations"), which purported to be made by the Yang di-Pertuan Agong under s. 2 of the Emergency (Essential Powers) Ordinance, 1969 ("the No 1 Ordinance"). The No 1 Ordinance was made on 15 May 1969 by the Yang di-Pertuan Agong in reliance upon the powers conferred upon him by Article 150(2) of the Federal Constitution. These powers had become exercisable, by virtue of a Proclamation of Emergency ("the Emergency Proclamation") issued by him on the same date under Article 150(1) of the Federal Constitution.

The Security Cases Regulations provide for a special procedure to be adopted in trials for security offences. It differs substantially from the procedure prescribed for the trial of capital offences under the Criminal Procedure Code. For the purposes of the instant appeal it is only necessary to mention that there is no preliminary inquiry before a magistrate and that the mode of trial is not by a jury in West Malaysia or by a judge with the aid of assessors in East Malaysia, but by a judge sitting alone.

In November 1976 the appellant was tried under this special procedure in the High Court in Malaya at Penang by a judge sitting alone. He was found guilty and sentenced to death. He appealed to the Federal Court upon a number of grounds of law. Their Lordships do not find it helpful to enumerate these, as a previous decision of the Federal Court delivered shortly before the hearing of the instant appeal, Public Prosecutor V. Khong Teng Khen & Anor. had made it impossible to argue successfully before the Federal Court a number of grounds of law which had been raised and decided in favour of the prosecution in the earlier appeal. The instant appeal is thus, in effect, an appeal against conclusions of law to be found in the judgment of the Federal Court in Public Prosecutor V. Khong Teng Khen & Anor. as well as in the instant case.

Their Lordships will find it convenient to marshal under three heads the questions of law which fall to be decided. The first is the validity of the Security Cases Regulations under the Constitution of Malaysia; the second is whether the Security Area Proclamation was still in force on 13 January 1976; the third is the legality under the Constitution of the decision of the Attorney General to prosecute the appellant for an offence under s. 57(1) of the Internal Security Act, 1960.

It is important to distinguish between the first head and the other two. If the appellant succeeds under the first head in establishing that the Regulations are void, the consequence will be that his trial by a judge sitting alone was a nullity; but unless he also succeeds under the second or the third head success under the first head would not necessarily preclude his being prosecuted for the same capital offence under the Internal Securit