remedy for the determination of these claims is no longer available, the Committee finds that it was incumbent upon counsel to raise them before the competent courts, provincial or federal, at the material time. This part of the author's allegations is therefore declared inadmissible under article 5, paragraph 2 (b), of the Optional Protocol. 14.2 If a State party extradites a person within its jurisdiction in such circumstances, and if, as a result, there is a real risk that his or her rights under the Covenant will be violated in another jurisdiction, the State party itself may be in violation of the Covenant. 15.1 With regard to a possible violation by Canada of article 6 of the Covenant by its decision to extradite Mr. Ng, two related questions arise: 13.5 It remains for the Committee to examine the author's claim that he is a "victim" within the meaning of the Optional Protocol because he was extradited to California on capital charges pending trial, without the assurances provided for in article 6 of the Extradition Treaty between Canada and the United States. In this connection, it is to be recalled that: (a) California had sought the author's extradition on charges which, if proven, carry the death penalty; (b) the United States requested Mr. Ng's extradition on those capital charges; (c) the extradition warrant documents the existence of a prima facie case against the author; (d) United States prosecutors involved in the case have stated that they would ask for the death penalty to be imposed; and (e) the State of California, when intervening before the Supreme Court of Canada, did not disavow the prosecutors' position. The Committee considers that these facts raise questions with regard to the scope of articles 6 and 7, in relation to which, on issues of admissibility alone, the Committee's jurisprudence is not dispositive. As indicated in the case of Kindler v. Canada,13 only an examination on the merits of the claims will enable the Committee to pronounce itself on the scope of these articles and to clarify the applicability of the Covenant and Optional Protocol to cases concerning extradition to face the death penalty. (a) Did the requirement under article 6, paragraph 1, to protect the right to life prohibit Canada from exposing a person within its jurisdiction to the real risk (i.e. a necessary and foreseeable consequence) of being sentenced to death and losing his life in circumstances incompatible with article 6 of the Covenant as a consequence of extradition to the United States? (b) Did the fact that Canada had abolished capital punishment except for certain military offences require Canada to refuse extradition or request assurances from the United States, as it was entitled to do under article 6 of the Extradition Treaty, that the death penalty would not be imposed against Mr. Ng? 15.2 Counsel claims that capital punishment must be viewed as a violation of article 6 of the Covenant "in all but the most horrendous cases of heinous crime; it can no longer be accepted as the standard penalty for murder". Counsel, however, does not substantiate this statement or link it to the specific circumstances of the present case. In reviewing the facts submitted by author's counsel and by the State party, the Committee notes that Mr. Ng was convicted of committing murder under aggravating circumstances; this would appear to bring the case within the scope of article 6, paragraph 2, of the Covenant. In this connection the Committee recalls that it is not a "fourth instance" and that it is not within its competence under the Optional Protocol to review sentences of the courts of States. This limitation of competence applies a fortiori where the proceedings take place in a State that is not party to the Optional Protocol. 14.1 Before addressing the merits of the communication, the Committee observes that what is at issue is not whether Mr. Ng's rights have been or are likely to be violated by the United States, which is not a State party to the Optional Protocol, but whether by extraditing Mr. Ng to the United States, Canada exposed him to a real risk of a violation of his rights under the Covenant. States parties to the Covenant will also frequently be parties to bilateral treaty obligations, including those under extradition treaties. A State party to the Covenant must ensure that it carries out all its other legal commitments in a manner consistent with the Covenant. The startingpoint for consideration of this issue must be the State party's obligation, under article 2, paragraph 1, of the Covenant, namely, to ensure to all individuals within its territory and subject to its jurisdiction the rights recognized in the Covenant. The right to life is the most essential of these rights. 15.3 The Committee notes that article 6, paragraph 1, must be read together with article 6, paragraph 2, which does not prohibit the imposition of the death penalty for the most serious crimes. Canada did not itself charge Mr. Ng with capital offences, but extradited him to the United States, where he faces capital charges and the possible (and foreseeable) imposition of the death penalty. If Mr. Ng had been exposed, through extradition from Canada, to a real risk of a violation of article 6, paragraph 2, in the United States, this would have entailed a violation by Canada of its obligations under article 6, paragraph 1. Among the 13 See communication No. 470/1991, Views adopted on 30 July 1993, para. 12.3. 104