A federal judge has ruled against the NSA’s controversial collection of Americans’ phone records. The program was set to expire by the end of the month, but the ruling is considered a victory for civil liberties because it sets a legal precedent.

In his ruling on Monday, Judge Richard Leon of the US District Court reiterated his assertion that the NSA’s program “likely violates the Constitution” and said that “the loss of constitutional freedoms for even one day is a significant harm.”

In doing so, he sided with conservative legal activist Larry Klayman, whose clients had sued the NSA over its data collection following the revelations of whistleblower of Edward Snowden in 2013.

“This court simply cannot, and will not, allow the government to trump the Constitution merely because it suits the exigencies of the moment,” Leon wrote in his 43-page decision.