We've heard it a million times: the government failed to "connect the dots" after 9/11. While this is a very simplistic (and arguably false) summation of the main intelligence failures that led to the attacks, it has nonetheless largely shaped US intelligence and law enforcement policy in the ensuing decade plus.

One of the results of the endless propagation of this myth was the creation of so-called "intelligence fusion centers" throughout the United States, initially funded by the Department of Homeland Security. Now sustained by state and local governments, with occasional aid from DHS, fusion centers are staffed by representatives from federal, local, and state agencies, as well as members of private industry. They have cost the United States hundreds of millions of dollars over the last ten years, but even though they were set up as anti-terrorism intelligence offices, none has thus far produced any useful information about terrorism.

A congressional study found the centers were hemorrhaging money, duplicative of other federal counterterrorism programs (like JTTFs), and on top of all that, violative of civil liberties and civil rights. Our experience in Boston fits the bill. While the local fusion center didn't even know the FBI had investigated Tamerlan Tsarnaev, who is now suspected of having killed his best friend and two others in 2011 in a Boston suburb, its officers were busy spying on the Occupy Boston camp. We at the ACLU also discovered that the Boston Regional Intelligence Center (BRIC) was compiling so-called "intelligence reports" on peaceful protesters and dissidents. Groups like Veterans for Peace were marked with labels like "HOMESEC-DOMESTIC" and "EXTREMISTS".

Advocates at places like the ACLU have been working for years to try to understand exactly what kind of information sharing goes on at fusion centers. Through programs like the "suspicious activity reporting" operation, state and local police send almost entirely useless information up the chain to federal officials. But what of the information that comes from the top, down to the local level?

We know that police and other local officials stationed at fusion centers have access to FBI databases like eGuardian, but what about NSA information? To what extent is illegal dragnet surveillance conducted by military intelligence trickling down to state and local police officers in our communities?

Unfortunately, almost a year after Edward Snowden's leaks began trickling out, we still don't have a concrete answer to that question. It's becoming more obvious that the once solid wall that stood between criminal investigations and foreign intelligence is crumbling. But how fast is this happening, and in exactly what way?

We know that the FBI increasingly has access to the vast troves of information the NSA harvests about our innocent phone calls, location histories, and internet activity. But what about the sprawling DHS? And what about the state and local police officers who work with DHS analysts at fusion centers nationwide? Is any of the information NSA collects being used in local intelligence or criminal investigations, in secret and in a way that's purposefully hidden from defendants and even judges?

According to the slide embedded above, NSA counts DHS as one of its domestic intelligence "customers". We desperately need answers about exactly what that means. Right now we just have a lot of questions.