Yahoo has been accused of supplying information to China which led to the jailing of a journalist for "divulging state secrets". Yahoo said it had to operate within each country's laws.
Just like Yahoo!, Google can also become a "police informant" but for a noble and good cause - it can help the government catching software pirates who run warez websites from China providing illegal software downloads.
In the picture below, a warez website located in China is shown serving Google Ads (highlighted in yellow) Google Adsense policies prohibit ads on sites with Hacking/cracking content. How did this particular warez site trick Google Adsense is also an issue.
Since Google would have the full address details of the adsense publisher, it is actually very easy to catch the software piracy gang but only if the Government is willing.