A U.N. panel of independent legal experts is demanding that China immediately free Nobel Peace laureate Liu Xiaobo and his wife and pay them "adequate" compensation.
The Working Group on Arbitrary Detention issued separate opinions saying China is violating international law by imprisoning Liu and holding his wife, Liu Xia, under house arrest.
Freedom Now, a Washington-based human rights group whose founder, Jared Genser, is the lead lawyer for the Lius, released the opinions on Monday.
The U.S. government strongly backed the Working Group's opinions.
"We join in with the U.N. Working Group, and once again call for the immediate release of Liu Xiaobo, as well as his wife, from detention, with full restoration of their rights, and urge China to uphold its international human rights obligations," U.S. State Department spokesman Mark Toner said in Washington.
The five-member Working Group, established in 1991 to investigate instances of alleged arbitrary deprivation of liberty, reports to the Geneva-based U.N. Human Rights Council. It can give opinions, but neither the group nor the Human Rights Council have power to enforce them.
Liu, winner of the 2010 Nobel Peace Prize, was arrested in December 2008 and sentenced in December 2009 to 11 years in prison for "inciting subversion of state power."
A prominent intellectual and democracy activist, he was co-author of Charter 08, a manifesto that called for an end to single-party rule and advocated peaceful reforms based on freedom, democracy and the rule of law.
His wife, a poet and painter, has not be charged with any crime, but since Liu's award was announced on Oct. 8, 2010, she has been under house arrest with limited movement and no communication with the outside world.
In the case of Liu, the Working Group said in its opinion that China violated bans in the Universal Declaration of Human Rights against arbitrary arrest and detention as well as its guarantee of the right to a fair trial and freedom of opinion and expression.
China argued in an April 13 submission to the group that its citizens enjoy the right to freedom of speech, including the right to criticize the government. But it said under the Constitution, freedom of speech may not "infringe upon the interests of the state," and all citizens must "safeguard the security, honor and interest of the motherland" and must not commit acts "detrimental to the security, honor and interests of the motherland."
China argued that under the International Covenant on Civil and Political Rights, which includes a provision allowing "certain restrictions" on the right to freedom of expression, its arrest of Liu is justified.
But the Working Group said restrictions of free speech "are strongly circumscribed" and concluded that "the government has not shown in this case a justification for the interference with Mr. Liu Xiaobo's political free speech." It also concluded that his arrest was unfair and that his trial, where the defense was given just 14 minutes to present its case, was conducted in a way "which constitutes a breach of fairness."
In the case of his wife, the Working Group said China stated "that no legal enforcement measure has been taken against Ms. Liu Xia."
The Working Group concluded that her house arrest "amounted to a detention" and that she "has the right to be brought promptly before a judge, and the right to legal counsel." It also concluded that she has been subject to arbitrary detention and denied the right to freedom of expression.
Freedom Now's Genser called the group's opinions "a critical affirmation from the United Nations that the Chinese government's detention of Dr. Liu and Liu Xia are in flagrant violation of international law."
"While the world's attention has shifted to the `Arab Spring,' these decisions are an important reminder that the crackdown against democracy activists _ and members of their families _ continues in China unabated," Genser said in a statement. "We call on the Chinese government today for Liu Xiaobo and Liu Xia's immediate release."
A spokesman for China's U.N. Mission, speaking anonymously because he was not authorized to speak publicly, said the mission didn't have any immediate comment on the opinions.
The working group includes chairman El Hadji Malick Sow of Senegal, vice-chair Shaheen Sardar Ali of Pakistan, Roberto Garreton of Chile, Vladimir Tochilovsky of Ukraine, and Mads Andenas of Norway.