CHEN GUANGCHENG, one of China’s best-known and bravest human rights activists, had been illegally and unjustly kept under house arrest in his village for 19 months when he somehow escaped last Sunday. He made his way to Beijing, and though his whereabouts are unconfirmed, activists reported Friday that he was under the protection of the U.S. Embassy. The State Department refused to respond to questions about him.

If the activists are right, as seems likely, the Obama administration faces difficult conversations with the Chinese government at a sensitive moment. But the principle it should adhere to is clear: It must be prepared to offer Mr. Chen refuge if he seeks it and refuse to allow his return to state custody — either official or unofficial.

Reasons for U.S. diplomats to wish Mr. Chen had taken his troubles elsewhere are numerous — and in some measure understandable. Secretary of State Hillary Rodham Clinton and Treasury Secretary Timothy Geithner are due in Beijing next week for an annual strategic and economic dialogue; the Obama administration is trying to maintain what recently have been relatively smooth relations with China as that country goes through what is looking like a bumpy leadership transition. Such considerations no doubt affected U.S. calculations when a deputy mayor from the city of Chongqing sought refuge in a consulate in February: The official eventually walked out of the consulate and was taken into custody by security forces dispatched from Beijing.

Mr. Chen’s case is different. The 40-year-old, self-educated lawyer, blind from birth, courageously undertook to defend women who were victims of forced sterilizations or abortions. He was arrested, tried on trumped-up charges of property destruction and blocking traffic, and sentenced to 51 months in prison. Since completing his term in September 2010, he has been held in his home by local security forces without charge or sentence. After he made a video about his situation last year, he and his wife were severely beaten.

Mr. Chen’s family is now in danger. Activists say his wife and daughter have been confined to their home, and his brother and nephew have been arrested. No doubt authorities are embarrassed by Mr. Chen’s escape, but he and his family have committed no crime and deserve no punishment.

It is not clear if Mr. Chen is seeking asylum in the United States. Activists in touch with him say he wishes only to be allowed to live legally and in peace in China, and that he is reluctant to leave the country. But Mr. Chen clearly qualifies for political asylum, and there is a precedent for the U.S. Embassy in Beijing serving as a harbor for a dissident — Fang Lizhi, who lived there for a year following the 1989 Tiananmen square crackdown.

As U.S. Ambassador Gary Locke pointed out in January, China’s respect for human rights “is in a down period, and it’s getting worse.” Ms. Clinton mentioned Mr. Chen by name in a speech last November in which she called on Beijing “to embrace a different path.”

Well-timed or not, the administration’s handling of this affair may tell the new Chinese leadership, and the rest of the world, whether the United States is serious about defending those who seek to push China toward that different path.

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