Google gets warrants to hand over data, just like everyone else. There are some differences however in how Google handles government requests.
1. Google tries to be very transparent about what requests they get from the government, and how much they are forced to hand over.
2. When George W. Bush asked for search data tied to IP addresses, all the major search provides just handed it over without a warrant and Google refused. Google's response was to go one step further and alter their policies to anonymize their logs even sooner to help protect their users.
3. Google has even considered moving data centers to the ocean to keep your private data away from government demands.