Many of the lawyers have taken on cases, involving issues like Tibetan political activism and police brutality, that gained national and even international attention. The advocacy groups, Human Rights Watch and Chinese Human Rights Defenders, called the actions by the legal authorities part of an effort to intimidate the lawyers and their law firms into avoiding sensitive cases.

“It is unprecedented to have so many prominent lawyers facing difficulties with their license renewal,” Nicholas Bequelin, a Hong Kong-based researcher with Human Rights Watch, said in a telephone interview on Wednesday. “This is a sort of backhand retaliation by judicial authorities in Beijing to warn the firms that employ these lawyers that there might be consequences to their business if they don’t keep their distance.”

The authorities in China have frequently sought to silence or intimidate activist lawyers by holding up the annual renewal of their licenses to practice law. But the widespread use of the bureaucratic technique against top lawyers in the capital is rare.

With China entering the four-day Dragon Boat Festival national holiday weekend, Beijing judicial officials were unavailable for comment on the charges on Wednesday. The Associated Press reported that its request for comment, faxed to the city’s Justice Bureau, had not been answered by evening. Mr. Bequelin said that in four cases, Beijing judicial authorities had told the heads of law firms that a civil rights lawyer in their practice faced difficulties in renewing a license.

In some cases, the law firms were told that they could avoid difficulties by giving the lawyers failing grades in their annual performance evaluations, a move that would give the authorities ammunition in any move to permanently disbar them.

In other cases, the warning was delivered either directly to the lawyers or to officials in the city bar association, which is effectively government-controlled. In turn, the bar association has told the lawyers that the renewals of their association memberships are problematic.

Two other civil rights lawyers who practice outside Beijing have also been warned that their licenses are in peril, the two advocacy groups stated in press releases.

The 20 lawyers listed by the two groups have pursued a broad range of cases in the last year that either challenged the government directly or threatened to cause embarrassment. Among other causes, they have represented the families of schoolchildren killed during last May’s Sichuan earthquake; the families of children injured after drinking milk tainted with the industrial chemical melamine; Tibetans arrested during the March 2008 antigovernment protests; and members of the Falun Gong sect, which the government has labeled a dangerous religious cult.

Some of those threatened have been attacked and beaten as well.

Cheng Hai, a lawyer, was beaten last month in Chengdu, in southwestern Sichuan Province, while investigating the case of a student and Falun Gong practitioner who had been imprisoned on charges of “publicizing an evil cult.” Two others, Zhang Kai and Li Chunfu, were arrested and beaten by police officers this month while investigating the case of a man who had died during his sentence in a camp for re-education through labor.

Government pressure on activist lawyers appears to be increasing this year, Chinese Human Rights Defenders stated, as Chinese officials seek to guarantee public order during a stretch of politically sensitive dates, including the 20th anniversary of the bloody assault on Tiananmen Square pro-democracy demonstrators on June 4.

http://www.nytimes.com/2009/05/28/world/asia/28china.html?_r=1&ref=asia