Microsoft was accused this week of extending the Chinese government's internet censorship regime to the rest of the world through its Bing search engine. I don't believe that Microsoft intended to do that, but the company is by no means off the hook.

After conducting my own research, running my own tests, and drawing upon nearly a decade of experience studying Chinese internet censorship, I have concluded that what several activists and journalists have described as censorship on Bing is actually what one might call "second hand censorship". Basically, Microsoft failed to consider the consequences of blindly applying apolitical mathematical algorithms to politically manipulated and censored web content.

From my desk in Washington DC, when I enter terms into Bing in simplified Chinese (the written language used primarily in mainland China) on subjects the Chinese government censors heavily like "Dalai Lama", the links I get from Bing are mainly from websites created and run from mainland China. In accordance to Chinese government requirements, they are all censored and skewed to favor the Chinese Communist Party's worldview. However when I enter "Dalai Lama" in traditional Chinese characters (used mainly in Hong Kong, Taiwan, and other Chinese communities outside of mainland China) I get almost entirely non-mainland content including Tibetan exile websites and others supporting the Dalai Lama.

Then I search "Dalai Lama" in both simplified and traditional Chinese characters on Google. The results also differ for each because the traditional search favors content from Hong Kong and Taiwan. But Google's top simplified Chinese results nonetheless include links to websites created and operated by organizations based outside of China – like Wikipedia, Voice of America and exiled Tibetan organizations.

Search algorithms are indeed complicated and no company gives away its "secret sauce". But they all rely heavily on the number of inbound links to a website as well as its "click through" traffic numbers. The reality is that due to the massive size of China's internet users, incoming links and click-throughs for the most popular mainland-based websites can be orders of magnitude greater than some the most popular websites in North America and western Europe. Websites contradicting the CCP's worldview tend to be blocked in mainland China, which means that the number of people clicking through to simplified Chinese language websites based outside of China is inevitably lower.

The algorithm deployed by Bing may be mathematically sound, but it fails to protect online freedom of expression. Bing failed to take into account the political reality of Chinese government censorship and its broader impact on the shape of the Chinese internet. Without adjustments to how simplified Chinese websites based outside of mainland China are "weighted," exiled and dissident online voices inevitably lose out. Put it another way: an apolitical mathematical formula automatically amplifies Chinese government censorship to all people searching for simplified Chinese content anywhere in the world, not just in China.

Google apparently identified this problem some years ago and found a solution. Most likely that solution involved some mathematical means of compensating for the traffic imbalance between websites located inside mainland China (with critical content deleted) and those simplified Chinese websites based outside of China that are blocked – and thus denied the same levels of traffic and links from China's nearly 600 million internet users. It's not clear why Microsoft didn't take the problem more seriously when it was first identified in 2009 by New York Times columnist Nicholas Kristof. Microsoft claimed then that it was working to address what it described as technical issues. One charitable theory might be that its engineers got busy with other priorities and their managers forgot to follow up, and no reporters or activists reminded them about the problem again – until now.

As a member of the Global Network Initiative, Microsoft has made clear commitments to freedom of expression and privacy. It just underwent an assessment certifying that it has put policies and practices in place to respect users' rights. It is part of a coalition fighting hard against the NSA's abuse of surveillance powers. It recently overhauled the way that Skype works in China to boost user privacy protections. For now, I am giving the company the benefit of the doubt.

But if Microsoft wants people to believe its denials of active censorship, it must be more transparent about how Bing interacts with governments. A first step would be to follow Google's example and publish a "Transparency Report" with data on the number of government censorship requests Bing receives – and complies with – around the world. Even more urgently, Bing must bring its technical systems and algorithms into better alignment with Microsoft's human rights commitments.