Google has issued a stinging rebuke to the US government's legal request for copies of all search terms used, and the URLs they identify, over a two-month period.

The US Department of Justice filed a legal case against the search firm last month after it refused to hand over the data, which the government is seeking to help devise a law that would protect children from internet pornography.

Google's legal response describes the government's request as "so uninformed as to be nonsensical". 

"The very fact that the government is so uninformed about the value of search and URL information, and so dismissive of Google's interest in protecting it, speaks volumes about why the court should protect Google from this compelled disclosure," stated the brief filed by lawyers at legal firm Perkins Coie.

"The government's cavalier attitude undermines any credibility in the assertion it later makes that it can or will protect Google against loss or further disclosure of the information, a promise that is hollow in the context of litigation in any event."

Google received a subpoena for the data from the Department of Justice on 25 August 2005 and has been fighting the case ever since.

MSN and Yahoo have handed over the information but Ask Jeeves, the fourth most popular search site in the US, has not been asked.

Google is fighting the case on three fronts, insisting that the information is useless for the proposed task; that disclosure would reveal trade secrets and lead to loss of business; and that the order would place an undue burden on the company.