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Chinese Knife law
Widely speaking, the knives in China are extremely restricted. There is a public safety regulation especially deal with the sharpen stuff, which is covering almost all the knives in common sense. The regulations can be slightly different with different city, so I wouldn't call it a law. The main contents of those regulaitons basicly are same because they are instructed by one documents from Ministry of Justice of China.
The regulation gives the size, type and pattern of the knives which have been called controlled knives. In the newest version, there are five type of knives are controlled.
First, dagger, dirk or stylet with a 100mm or longer blade. Whatever you called, this type of knives usually have obvious crosspiece between the handle and blade.
Second, the triangular bladed mechanical knives. Like Shing's sleeve dagger but widely used in the mechanical work.
Third, self-locking auto-knives with a 100mm or longer blade.
Forth, other single, double edge or pyramid blade knives with a 120 mm or longer blade and less than 60 degrees tip angle.
Fifth, the knives are restricted by other relative laws.
Unauthorized people are not allowed to carrying restricted knives to the public places.
The police have the rights to do the final judgement, which means if somebody was caught of carrying an restricted knife in a public place, there was no need to go to the court, the police officers will judge what kind of penalty should be, normally confiscate the knives, charge a fine around 30 pounds and/or up to 5-10 days custody. If they thought the person is not resipiscence or in some sensitive period, the penalty might much heaver than it should be.
About two month ago, Chinese polices started an action/operation to beat the carrying, having and unauthorized selling restricted knives. They will search those who are suspected to carrying the knives in public or having the knives in home. During this period, they will give the heavest penalty and now the action is in its peak period, most of the fans changed the topics in the forums and also their EDCs.