A US federal judge has ruled that mass government surveillance of the phone network is legal, a week after another court said the opposite.
New York District Judge William Pauley described the snooping as a "counter-punch" against al-Qaeda.
He said the National Security Agency programme might even have prevented the 9/11 attacks.
Last week a Washington DC federal judge ruled the surveillance was "likely unconstitutional" and "Orwellian".
But in yeterday’s decision, Judge Pauley, of the US District Court for the Southern District of New York, said "the balance of equities and the public interest tilt firmly in favour of the Government's position".