The government is studying whether there is a need to incorporate relevant mainland Chinese laws into Annex III of the Basic Law in order to allow a joint Hong Kong-mainland checkpoint arrangement for the upcoming high speed rail West Kowloon Terminus. The shared immigration facility will mean passengers would do not have to leave the train for immigration after it crosses the Chinese border.
Lawmakers have said that the measure, if adopted, would harm the “one country, two systems” principle.
At a Legislative Council meeting on Wednesday, lawmaker Frederick Fung King-kee asked whether the authorities had plans to propose the measure to the Standing Committee of the National People’s Congress, so as to empower mainland personnel to enforce laws in Hong Kong.

Fung said the move may violate Article 18 of Hong Kong’s mini-constitution, the Basic Law, which states that “Laws listed in Annex III to this Law shall be confined to those relating to defence and foreign affairs as well as other matters outside the limits of the autonomy of the [Hong Kong Special Administrative] Region as specified by this Law.”
Secretary for Justice Rimsky Yuen Kwok-keung said that he was unable to see why the measure would violate the Basic Law or the “one country, two systems” principle.

Lawmaker Dennis Kwok Wing-hang said that it would be “dangerous” to include mainland laws in the Basic Law though the Annex III.
“Many [mainland] laws outside the limits of the autonomy of Hong Kong can be introduced, for instance, the national security law,” Kwok said.
He also questioned whether the crime of “Picking Quarrels and Provoking Troubles” in the mainland – often used to arrest activists – could also be introduced using the same method.
“To set a precedent like this for a rail link will seriously harm the ‘one country, two systems’ principle, and this is why the legal sector is worried,” Kwok added.
However, lawmaker Michael Tien Puk-sun disagreed, saying that some mainland laws were already present in the Annex III of the Basic Law.