For more than two decades, the Drug Enforcement Agency was running a mass surveillance program focused on telephony metadata—a program nearly identical to the one run out of the National Security Agency revealed by former contractor Edward Snowden.

A new report published on Tuesday by USA Today revealed that the DEA’s phone dragnet was halted following Snowden’s summer of leaks in 2013, but it has since taken a form markedly similar to what surveillance reform advocates have envisioned—at a minimum—for the NSA.

Beginning in 1992, the report revealed, the DEA was compelling phone companies to hand over the records of all calls originating from the United States to countries designated as harboring drug traffickers. During the program’s peak, that list contained more than100 different countries.

The program was authorized by President George H.W. Bush’s Justice Department, and not a single company challenged the orders in court.

For more than twenty years, the program churned on with little oversight, and eventually served as a “precursor” to the NSA’s ongoing post-9/11 bulk collection of Americans’ phone records.

The DEA databases were purged, however, and their collection efforts stopped in September 2013. The disclosure of its twin-spying program at the NSA, along with by persistent Reuters and the New York Times inquiries—led to its cessation.

While the administration publicly defends the NSA’s call records program, saying it is only used for counter-terrorism purposes, it found itself unable to back the same surveillance program for routine drug investigations.

“It was made abundantly clear that they couldn’t defend both programs,” a former Justice Department official told USA Today.

The department briefly tried to restart collection in December 2013, before adopting a new method that relied on the phone companies storing the records.

“Every day, the agency assembles a list of the telephone numbers its agents suspect may be tied to drug trafficking. Each day, it sends electronic subpoenas — sometimes listing more than a thousand numbers — to telephone companies seeking logs of international telephone calls linked to those numbers,” officials told USA Today.

The new process, which still resembles bulk collection, is similar to what President Obama first proposed more than a year ago as a remedy for the NSA’s phone metadata snooping

He called on Congress to pass legislation to codify the proposed transition of the program, but those efforts were sunk by a Republican filibuster during Congress’ 2014 lame-duck session.

In the meantime, the administration has actively reauthorized the program every three months. The most recent authorization lasts until the program’s legal underpinning, the PATRIOT Act, expires on June 1.

The DEA program, on the other hand, was quietly unwound and transitioned without any law from Congress, and without any knowledge of the public.

In January 2015, unnamed US security official told Reuters that the administration’s reluctance to unwind the NSA program stemmed from concerns it might lead to gaps in national security and increased costs.

Similarly, unnamed officials also told USA Today that, in the wake of transforming the DEA’s collection, results are “more targeted,” but also “slower and more expensive.”

The effectiveness of bulk surveillance in general is questionable.

Administration officials have painstakingly tried to provide examples in which the intrusive spy tools were justified because they stopped potential terrorists, but have been unsuccessful. Former DEA officials admitted to USA Today that before that agency’s program was dissolved it was “suffering from diminishing returns.”

When it comes to bulk collection, phone metadata is only piece of the puzzle for the NSA. The agency also has authorities to collect en masse Internet data, financial transaction records, and other information useful to mosaic investigations.