The American Civil Liberties Union gave notice on Thursday that it will continue its legal case challenging the constitutionality of the National Security Agency’s collection of all US phone records, drawing the federal appeals courts into a decision on the controversial surveillance.

A federal judge in New York, William Pauley, gave the NSA a critical courtroom victory last week when he found the ACLU “has no traction” in arguing that intercepting the records of every phone call made in the United States is a violation of the constitutional protection against unreasonable search and seizures.

As expected, on Thursday the ACLU filed notice that it will appeal Pauley’s decision before the second circuit court of appeals. The civil liberties group said in a statement that it anticipates making its case before the appellate court in the spring.

“The government has a legitimate interest in tracking the associations of suspected terrorists, but tracking those associations does not require the government to subject every citizen to permanent surveillance,” deputy ACLU legal director Jameel Jaffer said in the statement.

Appealing Pauley’s decision in ACLU v Clapper adds to the pressure on federal judges, and possibly the supreme court, to adjudicate a surveillance controversy that has engulfed the Obama administration and US intelligence agencies.

The Justice Department is widely expected to appeal its own recent legal setback in a different case. On 16 December, Judge Richard Leon ruled that the “almost Orwellian” bulk surveillance likely violated the same constitutional prohibition on overbroad searches.

While both sides now look to the appellate courts to settle the threshold issue of the constitutionality of the bulk surveillance effort, it is likely that the losing sides will attempt to convince the supreme court to settle the question.

Pauley wrote in his 27 December ruling that the wisdom of the surveillance is a policy decision that the political branches of government ought to resolve. Legislation to end domestic bulk collection awaits Congress when it returns from its holiday recess, and proponents hope that the skepticism of a recent White House review panel fuels its prospects.

The ACLU’s appeals notice came as both the New York Times and the Guardian editorialized in favor of a pardon for Edward Snowden, the former NSA contractor whose exposure of the bulk phone records collection and other NSA activities has upended the intelligence world.

The White House is on record as opposing a pardon. The Justice Department filed a criminal complaint against Snowden on espionage charges in June, although there has not been any public indictment of Snowden to follow.

Representative Peter King, a New York Republican and a member of the House intelligence committee, blasted the Times as a “blame America first rag” that goes “out of their way as to be apologists for terrorists”. King has previously defended the Irish Republican Army.

Representative Alan Grayson, a Florida Democrat, tweeted “give him clemency”, in response to the media push for leniency for the NSA whistleblower.

In addition to the ACLU case and the one recently ruled on by Leon, a third court, in California, is considering a challenge to the bulk surveillance, in a case known as First Unitarian Church of Los Angeles v NSA.