Since 2008, warrantless wiretaps have been a part of the United States' counterterrorism efforts, but targets of those wiretaps were never informed where evidence against them originated. That may change in the next couple of weeks. According to The New York Times, prosecutors from the Justice Department plan to inform a defendant that the evidence being used again him originated from warrantless surveillance. A public admission such as this could potentially open the door for a judicial review of the surveillance law's constitutionality.

The shift comes following internal debate in the Justice Department, where Solicitor General Donald Verrilli Jr. argued that there was no legal justification for withholding the sources of evidence. The Justice Department first acknowledged its intention to inform defendants back at the end of July.

The issue also came to Verrilli's attention after Senator Diane Feinstein, the Intelligence Committee Chair, cited examples of the surveillance program working. Lawyers for two of the cases Feinstein brought up asked for an explanation of where evidence against their clients had originated, but were rebuffed. Prosecutors have since made new court filings stating that they will not use any evidence gathered under the 2008 law.

Back in February, the Supreme Court halted a challenge to the law led by the ACLU in a 5-4 decision, and concluded, "that, because the eavesdropping is done secretly, the American Civil Liberties Union, journalists and human-rights groups that sued to nullify the law have no legal standing to sue — because they have no evidence they are being targeted by the FISA Amendments Act." Now that the warrantless surveillance activities may be disclosed to defendants, a challenge to the program's constitutionality could once again make its way to the Supreme Court.