Editor's note: Huo Zhengxin is a professor of law at the China University of Political Science and Law. The article reflects the author's opinions, and not necessarily the views of CGTN.

On May 28, 2020, the National People's Congress (NPC) of the People's Republic of China (PRC) approved a decision to establish and improve the legal system and enforcement mechanisms for the Hong Kong Special Administrative Region (HKSAR) to safeguard national security.

Though the decision states clearly that it aims to uphold and improve the "One Country, Two Systems" policy, some Western countries, represented by the Group of 7 leading industrialized nations, expressed their "grave concern," and alleged that China's decision to impose the national security law on the HKSAR "lies in direct conflict with its international obligations under the principles of the legally-binding, UN-registered Sino-British Joint Declaration."

The European Parliament went even further by adopting a resolution calling for the European Union to bring China to the International Court of Justice, accusing China of violating the Joint Declaration.

Is the Joint Declaration relevant to national security law in HKSAR? Does China's decision to impose the national security law on the HKSAR violate the instrument?

First, as a threshold matter, it is necessary to determine the rights and duties of the parties under Joint Declaration.The Joint Declaration itself contains eight paragraphs. Paragraph 1 stated that China would resume the exercise of its sovereignty over Hong Kong from July 1, 1997. Paragraph 2 proclaimed that the UK would hand over Hong Kong to China on July 1, 1997. Paragraph 3 set forth the basic policies of China regarding Hong Kong in 12 subparagraphs. The policies set out in this paragraph are further elaborated by the Chinese government in Annex I. Paragraphs 4 to 6 and Annex II and III stipulate arrangements during the transitional period. Paragraphs 7 and 8 are about the Joint Declaration's implementation and entry into force. My analysis is that after the smooth transfer of sovereignty of Hong Kong from the UK to China on July 1, 1997, the eight paragraphs contained in the declaration were all fulfilled.

Therefore, after the execution of all paragraphs of the Joint Declaration, the UK has no sovereignty, jurisdiction or "right of supervision" over Hong Kong any more. The UK alleges that China's decision to enact a national security law for Hong Kong is in conflict with the Joint Declaration; however, it fails to explain persuasively why such a decision violates China's obligation under the instrument, nor is it able to elaborate which obligation or obligations is/are breached by the decision in question.

On the contrary, a careful reading of the Joint Declaration can lead to the conclusion that there exists no direct legal obstacle for China to impose the national security law on the HKSAR as long as the law does not contradict China's basic policies regarding Hong Kong set out in Paragraph 3 and Annex I. As a matter of fact, as the law is still in the process of legislation whose draft has yet to be finalized, the UK's allegation, needless to say, is unsubstantiated, which may be compared to a "presumption of guilt."

What's more, apart from the UK, some other Western countries, the U.S. in particular, are actively engaged in Hong Kong affairs. Nonetheless, it has to be stressed that the U.S. has no right to supervise the implementation of the Joint Declaration, nor is it entitled to interfere with Hong Kong affairs. The maxim pacta tertiis nec nocent nec prosunt expresses the fundamental principle that a treaty applies only between the parties to it. Therefore, the U.S. does not, and should not, have the right to monitor the implementation of the Joint Declaration to which it is not a party. Moreover, as the prohibition of intervention is a corollary of every state's right to sovereignty, territorial integrity and political independence, the U.S. is not allowed by international law to interfere with Hong Kong affairs.

Some Western countries also argue that the Basic Law of the HKSAR is a product of the Sino-British Joint Declaration; in other words, the former is the legal basis or source of the latter. However, such an argument does not hold water.

In the first place, the Constitution of the PRC makes it clear that the Constitution itself is the legal basis for the establishment of special administrative regions and the formulation of the Basic Law of the HKSAR.

The currently effective Constitution of the PRC was enacted in 1982, two years earlier than the conclusion of the Joint Declaration. Article 31 of the Constitution provides that "[T]he state may establish special administrative regions when necessary. The systems to be instituted in special administrative regions shall be prescribed by law enacted by the National People's Congress in the light of specific conditions." This article manifests that the Constitution is the legal basis for the establishment of special administrative regions and the formulation of the Basic Law of the HKSAR as well as that of the Macao SAR.

Second, the Joint Declaration itself proclaims that the Constitution of the PRC is the legal basis for the Basic Law of the HKSAR. The Chinese government elaborates the basic policies of China regarding Hong Kong in Annex I where it pronounces unambitiously that "[T]he National People's Congress of the People's Republic of China shall enact and promulgate a Basic Law of the Hong Kong Special Administrative Region of the People's Republic of China in accordance with the Constitution of the People's Republic of China."

Last, but not least, the Basic Law of the HKSAR affirms that the Constitution of the PRC is its legal basis, as the last paragraph of its preamble states that "[I]n accordance with the Constitution of the People's Republic of China, the National People's Congress hereby enacts the Basic Law of the Hong Kong Special Administrative Region of the People's Republic of China."

Therefore, it is the Constitution of the PRC, rather than the Joint Declaration, that forms the legal basis for the establishment of special administrative regions and the formulation of the Basic Law of the Hong Kong SAR.

After a systematic examination of the above issues relating to the Joint Declaration in terms of international law, the questions raised in the beginning of the article can now be answered in a definite manner: the Joint Declaration is NOT relevant to the national security law in Hong Kong.

As long as the law is enacted and promulgated pursuant to the Constitution of the PRC and the Basic Law of the HKSAR, its legitimacy cannot be challenged. Foreign countries are not entitled to interfere with China's decision to impose the national security law on the HKSAR on the grounds of the Joint Declaration.

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