Chinese officials like to say that other countries should respect China's "judicial sovereignty."

Well, the judicial system will certainly earn more respect if it were independent of the government and of the Communist Party and if defendants are given the rights set out in the law.

But Ai Weiwei's detention shows that such is not the case. Last Thursday, the Foreign Ministry spokesman said that "Ai Weiwei is under investigation on suspicion of economic crimes" and that the case "has nothing to do with human rights or freedom of expression."

Curiously, while the foreign ministry spokesman seemed to possess information on the case, the same has not been shared with the artist's lawyer or his family.

That suggests at the very least that the case is being handled politically.

Also curiously, while eight questions were asked about the Ai case at the press conference, none of the questions and answers appears in the transcript of the press conference on the ministry's website.

Perhaps the government realized afterwards that having the foreign ministry spokesman expound on the issue while the procuratorate and the courts are silent sent out the wrong message about China's "judicial sovereignty."

But, at least, it appears that the Chinese authorities may present charges against Ai-or release him-after their investigations. And that the judicial system may be involved.

Such is not the case with many other human rights cases. The U.S. State Department's 2010 report talks about extrajudicial killings, including executions without due process. In addition, there is extrajudicial detention, extortion and assault.

"Efforts to silence political activists and public interest lawyers were stepped up," the report said, "and increasingly the government resorted to extralegal measures including enforced disappearance, 'soft detention,' and strict house arrest, including house arrest of family members, to prevent the public voicing of independent opinions."

One example of house arrest is that of Chen Guangcheng, the human rights lawyer who, after completing a sentence of 40 months on charges of "disrupting traffic," has been held with his wife and child without benefit of any legal process.

The fact that the authorities resort to extralegal measures is not denied even by the official Chinese press. The China Daily, for example, reported last October on "black jails" in which petitioners are illegally held.

So the Chinese authorities themselves are violating the law and, in effect, showing contempt for the judiciary by bypassing the court system.

Worse than house arrest is the increasingly common phenomenon of someone simply disappearing as security authorities whisk him or her away without informing the family and without any legal procedures.

So many people in China are "disappearing" that a United Nations unit-the Working Group on Enforced or Involuntary Disappearances-on Friday issued a statement in which it expressed "serious concern at the recent wave of enforced disappearances" in China, pointing out that "enforced disappearance is a crime under international law."

According to the working group, "persons subject to enforced disappearances appear to be human rights activists, lawyers and students. These enforced disappearances represent the continuation of a disturbing trend in the suppression of dissidents."

Last year, the working group called on China to explain the disappearance of the prominent human rights lawyer Gao Zhisheng but received no response. Later, reporters were told to respect China's "judicial sovereignty" and that "China is a country under the rule of law."

Attempts to get the Chinese government to disclose the whereabouts of Gao have failed. However, in January 2010, while Gao was missing, the foreign ministry acknowledged that he was being held by the authorities, with the spokesman saying, "This person, according to Chinese law, is where he should be."

So, it seems, Chinese law justifies the "disappearance" of individuals even though international law deems it to be a crime.

This being the case, it is little wonder that China's "judicial sovereignty" is not universally respected.