As the first high speed train pulls out of Hong Kong's West Kowloon Station early Sunday morning to mainland China, it will cement a major change to the autonomous city's relationship with Beijing due to an unprecedented immigration deal, according to lawmakers and legal experts.
Much of the concern is centered on an important feature of the HK86.42 billion ($11 billion) rail link, which has given China legal jurisdiction over part of the train station and the entire rail link, an arrangement known "co-location."
It's a deal the Hong Kong government has said will ease immigration procedures, allowing travelers to go onto any Chinese city along the rail line. It's similar, they also say, to arrangements that exist between the United States and Canada, where travelers go through immigration in places like the Montreal airport before flying onto New York, according to promotional information on the rail line.
But legal experts like Philip Dykes, chairman of the Hong Kong Bar Association, said the agreement differs in small but crucial ways from other countries, beginning with the full powers given to Chinese immigration agents, which could have a serious impact on residents.
"What is different about the arrangements we have made here is that the Hong Kong authorities have agreed that Chinese authorities may make full jurisdiction - that is to say not merely can they refuse entry but they can detain and remove," Dykes said.
"So Hong Kong residents, in fact anybody who may use the new facility, may cross a line marked in the station which marks the end of Hong Kong jurisdiction, pass over into mainland controlled area and if he or she falls foul of those authorities they may be detained and then taken away into the mainland."
While the powers of U.S. immigration agents in Canada were recently expanded, they are still significantly more limited than in Hong Kong, Dykes said. U.S. agents in Canada, for example, are not permitted to interrogate or arrest a traveler at their own discretion under Canada's Pre-clearance Act of 2016. Similar restrictions do not apply to Chinese agents in Hong Kong.
Then there is the fact that while the United States and Canada have comparable legal systems, Hong Kong and China differ in significant ways.
Hong Kong police, for example, can only hold someone for 72 hours without charge. In China, a suspect can be detained for up to 37 days without being arrested, after which time they may wait months before being formally charged.
But it's not just technical concerns, though, that have lawyers and pro-democratic legislators worried. They have also expressed deep concerns about what granting China a legal foothold in Hong Kong territory would mean long term for the former British colony.
One country, two systems
Under the terms of the return of Hong Kong to China in 1997, it is supposed to have separate rights and privileges until 2047 in an arrangement known as "one country, two systems." Many of these are spelled out in the Basic Law, including Article 18, which says no Chinese laws, with few exceptions, will apply on Hong Kong soil.
"Now what ever happened to ‘one country, two systems'? And you would say 'Oh it's just an arrangement, for the sake of they say for speed convenience, expediency. But then technically, a Hong Kong person within Hong Kong territory from now on if you go inside that station will not be able to apply for habeas corpus to Hong Kong courts because that's already Chinese territory," said Claudia Mo, a legislator for Kowloon West who has previously spoken out against the co-location agreement.
"Now they've done this, once they've done this, they can declare any space in Hong Kong, this legislature for example, Chinese territory and they can say mainland Chinese laws apply here. And this is just not right," she added.
The Hong Kong government directed VOA to a previous statement from late last year in response to questions on the co-location agreement. In the statement, the government said the Chinese "port area" of West Kowloon Station is legally "situated in the Mainland," Article 18 and the Basic Law do not apply in this case.
"For the high-speed rail passengers who use the procedures for exit and entry under the co-location arrangement, the procedures and their rights are basically the same as those under the traditional "separate location" arrangement," it said. "The main difference is that co-location arrangement is more convenient and efficient."
The immigration arrangement will be the subject of a legal case at Hong Kong's High Court on October 30.