Chinese officials, and those overseeing the security apparatus in particular, have long been suspicious of the efforts of lawyers to ensure that everyone is protected equally under the law. The ability of lawyers to practice has been curtailed, and some have been punished, particularly those championing issues related to civil rights and political expression. Some lawyers who were detained secretly during a broad security crackdown last year say they were beaten and tortured.

Several prominent rights lawyers have been subjected to lengthy and sometimes unexplained detentions, including Gao Zhisheng, who was initially convicted of inciting subversion in 2006 and is now in prison in Xinjiang; Chen Guangcheng, who has been forcibly confined to his home in Shandong Province with his wife and daughter since completing a four-year, three-month prison term in September 2010; and Jiang Tianyong, who said he was tortured during an illegal two-month detention last year.

On Wednesday, the Justice Ministry posted an explanation with the oath that said its goal was to, among other things, ensure that lawyers followed the core values of “loyalty, devotion to the people, justice and probity.” The aim of the oath is also to “effectively improve the ideological and political quality, professional ethics and skills of lawyers.”

But some critics said the oath was a farce. “The oath itself is full of contradictions,” said Pu Zhiqiang, a lawyer who has represented Lu Qing, the wife of Ai Weiwei, the rebel artist who was detained without charge in two secret locations for 81 days last year. “Lawyers swear loyalty to the party and to the sanctity of the law? We all know that the party’s interference is often the reason why the law can’t be implemented.”

Politics and the law are inseparable under Communist rule. This month, there was much debate during the National People’s Congress over proposed revisions to the criminal procedure law. Legislators eventually passed a law that had one notable victory for legal reformers and rights lawyers: family members of detainees must be notified within 24 hours of the detention. But the police do not have to say where or why the person is being held, and the new law has been widely criticized for a clause that allows the police to hold a suspect in secret for up to six months in cases involving national security, terrorism or serious bribery. The police tend to define “national security” or “state security” in broad terms.