As a former US commerce secretary and governor of Washington state, Gary Locke wasn’t considered much of a heavyweight on human rights when he became the first Chinese-American ambassador to Beijing last year. Trade and maintaining smooth relations between Washington and its biggest foreign creditor were seen as dominating his agenda.

Yet, nine months on, Locke’s key role in the recent drama over blind legal activist Chen Guangcheng has put him on the front lines of US concerns about China’s embattled dissident community. Chen’s sudden escape from house arrest and a US decision to give him sanctuary in the US embassy gave Locke his first crisis as ambassador, made him a target of criticism from Beijing and earned him respect from the human rights lobby.

“He is setting a new precedent for future US ambassadors” on human rights, said Bob Fu of the Texas-based rights group ChinaAid, who has been…