Assistant Senate majority leader Richard Durbin is calling on leading Chinese Internet firm Baidu to protect human rights and stop censoring search results.
Durbin, a Democrat from the state of Illinois, on Wednesday released a copy of a letter he sent to Baidu chief executive Robin Li asking what plans Baidu has to protect freedom of expression.
Durbin also asked Li to reveal any plans Baidu might have to collaborate with California-based Facebook to launch an online social network in China.
"I appreciate that Baidu has given millions of Chinese citizens the ability to access information," Durbin said in his letter to Li.
"At the same time, your company has a moral obligation to respect fundamental human rights," he continued.
"This is particularly important in light of the Chinese government's recent crackdown on dissent, including the detention of many internet activists."
The senator said that he tested Baidu censorship for himself by using the search engine during a recent weeklong trip to China as part of a congressional delegation.
"I was disappointed, but not surprised, to see that Baidu heavily censors its search results," Durbin said in his letter.
He noted that Baidu benefited when Google essentially took itself out of the competition in China by defying censors.
Baidu's censorship work won it a "China Internet Self Discipline Award" from that government, according to the senator.
Durbin said he was concerned that a social network developed by Facebook and Baidu might be used as a tool by Chinese officials to track or find people whose viewpoints clash with the government's agenda.
The senator told Li that he was working on legislation that would hold technology companies with stock traded in the United States liable for not taking "reasonable steps" to protect human rights.
Baidu is listed on the Nasdaq exchange.
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