The internet search engine Google is resisting efforts by the US Department of Justice to force it to hand over data about what people are looking for.
Google has been resisting the government request since August
Google was asked for information on the types of query submitted over a week, and the websites included in its index.
The department wants the data to try to show in court it has the right approach in enforcing an online pornography law.
It says the order will not violate personal privacy, but Google says it is too broad and threatens trade secrets.
Privacy groups say any sample could reveal the identities of Google users indirectly. And they say the demand is a worrying precedent, because the government also wants to make more use of internet data for fighting crime and terrorism.
However, the Department of Justice has said that several of Google's main competitors have already complied.
The department first issued a request for the data last August.
- A list of terms entered into the search engine during an unspecified single week, potentially tens of millions of queries
- A million randomly selected web addresses from various Google databases.
The US government is seeking to defend the 1998 Child Online Protection Act, which has been blocked by the Supreme Court because of legal challenges over how it is enforced.
Google's refusal to comply prompted US Attorney General Alberto Gonzales to ask a federal judge in the state of California on Wednesday for an order to hand over the records.
But Google's lawyers said it would fight the order.
"Google is not a party to this lawsuit and their demand for information overreaches," associate general counsel Nicole Wong said in a written statement.
"We had lengthy discussions with them to try to resolve this, but were not able to, and we intend to resist their motion vigorously."
Google has also said that providing the data would make its users think it was willing to reveal personal information about them, as well as giving competitors access to trade secrets.
One of its search rivals, Yahoo, said it had already complied with a similar government subpoena "on a limited basis and did not provide any personally identifiable information".
And Microsoft said in a statement that it "works closely with law enforcement officials worldwide to assist them when requested".
"It is our policy to respond to legal requests in a very responsive and timely manner in full compliance with applicable law," it said.