What is DAS (or Hemisphere), the massive call records surveillance program that runs through AT&T?

About a decade ago, the Edward Snowden leaks pulled back the curtain on the massive surveillance programs agencies like the NSA were conducting, shocking the world with their sophistication. Around the same time, an accidental discovery happened, revealing the Hemisphere program that allowed US law enforcement to obtain call record information for any phone number in the country, complete with history and additional metadata. Since being disclosed, the Hemisphere program was renamed to Data Analytical Services (DAS), and it apparently continues to operate to this day.

Like Fight Club, the first rule of Hemisphere is that you don’t talk about it. But law enforcement is still using it in investigations. Funding comes directly from the White House via a surveillance program that targets drug operations.

However, DAS/Hemisphere is apparently used in non-drug-related investigations. The newest report on DAS/Hemisphere comes from . The blog picked up a letter that US Senator Ron Wyden sent to the Department of Justice (DOJ), challenging the program’s legality.

But it was that first detailed Hemisphere in 2013. That’s the year when the program was supposedly named DAS. Sign up for the most interesting tech & entertainment news out there.

By signing up, I agree to the and have reviewed the Since then, conducted its own investigation into DAS/Hemisphere. Where does the money come from? reports that DAS/Hemisphere is part of a program called HIDATA that the White House’s Office of National Drug Control Policy (ONDCP) runs. HIDTA stands for “high-intensity drug trafficking area” and covers 33 regions of the US.

It started in 1990, and funding for HIDATA exceeded $280 million in 2020 alone. Comparatively, DAS/Hemisphere received $6. 1 million in “discretionary funding” from the White House since 2013.

Following story, Obama suspended funding in 2013. But law enforcement could still contact AT&T directly for the call records data. Funding resumed under Trump before being halted in 2021 when Biden took office.

However, President Biden’s administration resumed funding last year. I didn’t bring Edward Snowden’s whistleblowing by chance. Those revelations showed the various sophisticated instruments the NSA and others had on their hands to spy on others and their massive data collection capabilities.

DAS/Hemisphere might upset you after you hear what it can do, but it’s not quite as sophisticated. And it doesn’t collect the contents of calls made over cellular or landline. What can DAS/Hemisphere do? Per the EFF, DAS/Hemisphere can offer “information on phone numbers dialed and received, as well as the time, date, and length of call and in some instances location information.

” The EFF notes that the surveillance program has access to the telecommunication “switches” operated by AT&T. These guide telephone calls, which means AT&T collects call record data regardless of the carrier. However, law enforcement still has to generate subpoenas for AT&T to provide the call records information.

The same EFF says that some 4 billion call records could populate the Hemisphere databases as of 2015. Moreover, records can go back to 1987. The program does have a few interesting capabilities.

For example, when criminals drop their burner phones, DAS can operate an algorithm to find their new number. They can also discover additional phones a target might be using. The EFF also explains how law enforcement might work to conceal the existence of DAS/Hemisphere program from everyone involved in the legal process: Law enforcement hides Hemisphere through a practice called ‘parallel subpoenaing.

’ What that means is once police get results back from Hemisphere, they send another subpoena, this time directly to the suspect’s phone provider, to obtain the records for the new phone numbers identified by Hemisphere. The police are then careful to only reference this second request for records in their investigative reports, search warrant affidavits, and court testimony. Through this process, the original results returned by Hemisphere—and the process for obtaining them—are ‘walled off’ from judges, criminal defendants and the public.

Back to reporting, the blog provides a few examples of how law enforcement might use DAS/Hemisphere during investigations: In one instance, an officer with the Oakland Police Department asked for a ‘Hemisphere analysis’ to identify the phone number of a suspect by analyzing the calls of the suspect’s close friends. In another, a San Jose law enforcement officer asked the Northern California Regional Intelligence Center to identify a victim and material witness in an unspecified case. One officer, soliciting information from AT&T under the program, wrote: ‘We obtained six months of call data for [suspect]’s phone, as well as several close associations (his girlfriend, father, sister, mother).

’ The records do not indicate how AT&T responds to every request. The information comes from hundreds of gigabytes of data from law enforcement agencies that the Distributed Denial of Secrets published in 2020. What happens next? The , which I suggest you read in full , contains Senator Wyden’s letter to US Attorney General Merrick Garland.

This is the kind of letter that will need an official response, as Wyden is questioning the program’s legality. I’ll also point out the EFF’s on DAS/Hemisphere from previous years. With all that in mind, I’m sure the call records surveillance program will likely upset many, even though most people probably do not have anything to worry about.

Still, it’s the principle of the thing, especially if the surveillance program isn’t perfectly legal. Then again, law enforcement will use anything at its disposal to advance its investigations. I don’t think programs like DAS/Hemisphere will just cease to exist, not when all this call metadata is collected.

And, again, law enforcement agencies will still need subpoenas to access the data. .