A U.S. federal judge has ruled that the National Security Agency's telephone surveillance program is legal and useful in fighting terrorism.

District Judge William Pauley said in a written statement Friday that the bulk collection of telephone records is a “counter-punch” to terrorism that does not violate Americans’ privacy rights.

Pauley dismissed a lawsuit filed in Manhattan (New York) by the American Civil Liberties Union to challenge the program. His ruling contradicted an earlier decision by a district judge in Washington who said the NSA program was likely unconstitutional. That judge stayed the effect of his ruling, pending a government appeal.

Pauley said the mass collection of phone data “significantly increases the NSA’s capability to detect the faintest patterns left behind by individuals affiliated with foreign terrorist organizations.” He said the data collected by the NSA enables the agency to detect connections it might otherwise never be able to find. Citing the September 11th, 2001 terrorist attacks, Pauley said the cost of missing such connections can be horrific.

The NSA surveillance program was revealed earlier this year by former NSA contractor Edward Snowden, who took thousands of records from the agency. His disclosures about the government’s surveillance operations have angered many Americans concerned about privacy rights.

Snowden fled the country and is now living in Russia. He is wanted by the United States on charges of espionage.