A day after Reuters reported that the US Drug Enforcement Administration is using NSA surveillance data to apprehend suspects while hiding its sources, the Department of Justice has confirmed that it's aware of and examining these claims. In an email to The Guardian, the department said that it was "looking into the issues raised by this story," declining to comment further. Its comments corroborate those of press secretary Jay Carney, who also said yesterday that the Department of Justice was examining the allegations. Despite these comments, there's so far been no sign of an official investigation, and it's not necessarily clear what "looking into" means. So far, neither the DEA nor NSA have responded to our request for comment.

According to Reuters, the DEA was given tips from the NSA and other agencies through a unit called the Special Operations Division. This could include information that was gathered under the NSA's relatively permissive rules, which are meant to protect national security — not stop drug crimes. Reuters also reports that these tips aren't revealed in trials. Instead, law enforcement uses a process known as "parallel construction," in which the real sources of information aren't revealed. That can mean that defendants aren't given access to all information about the case against them. And as revelations about the scope of NSA surveillance pile up, it also raises questions about just how that data is being used. If the Department of Justice does formally investigate, it will be cleaning its own house: the DEA itself is one of its subdivisions.