I think it’s helpful to always remember that as a visitor to China, they probably know everything there is to know about you, and where you are every second of the day. If you could be used for any Geo political, humanitarian, or financial leverage, you should probably consider that the country is going to arrest you and do that
> China has rejected the label of “hostage diplomacy” as “totally groundless,” saying that no one who follows the country’s laws should fear arrest
[..]
> Still, Chinese diplomats have indicated the fates of the two Canadians detained on Dec. 10, 2018 -- days after Meng’s arrest -- were open to negotiation. Zhao Lijian, another Foreign Ministry spokesman, told a briefing in June that political intervention to stop proceedings against Meng “could open up space for resolution to the situation” of the Canadians
That pretty much says it all.
And "the country’s laws" are whatever the CCP says they are, whenever they feel like telling somebody. Or not.