More than 13 years ago, as the US government struggled to figure out what to do with hundreds of "suspected terrorists" it either captured or acquired in exchange for bounties, someone in the Bush administration floated the idea of shipping them to the US naval base at Guantanamo Bay.

"It's the legal equivalent of outer space," one official remarked.

A young Justice Department attorney named John Yoo agreed. He wrote a legal memo for the Pentagon's top attorney on December 28, 2001 and explained that while the lease agreement gave the US "complete jurisdiction and control" of Guantanamo, it was still outside American sovereignty due to its location in Cuba. In other words, neither US nor Cuban courts would have jurisdiction over detainees held there if they tried to challenge the legality of their detention.

The day before Yoo finished writing the legal memo, then-Secretary of Defense Donald Rumsfeld explained to reporters why the Bush administration had settled on detaining "war on terror" captives at Guantanamo. "I would characterize Guantanamo Bay, Cuba, as the least worst place we could have selected. It has disadvantages.... Its disadvantages, however, seem to be modest relative to the alternatives."

The public was told by Rumsfeld and other top Bush administration officials that Guantanamo was needed because the men who were sent there were the "worst of the worst," the "sort of people who would chew through a hydraulics cable to bring a C-17 [transport plane] down."

But according to a new report, there was an ulterior motive for setting up Guantanamo: It was the ideal long-term interrogation facility, a "battle lab" where detainees would be subjected to untested interrogation methods and "exploited" for their intelligence value in what turned out to be a massive "experiment."

The claims in the 66-page report, "Guantanamo: America's Battle Lab," prepared by Seton Hall Law School Center for Policy & Research and shared with VICE News, aren't new. In 2009, the Senate Armed Services Committee released the findings of its investigation about the treatment of detainees in custody of the US military and reached similar conclusions.

'The laboratory paved the way for a multitude of psychological experiments against detainees who were admittedly not the worst of the worst.'

But the Seton Hall study, co-authored by the university's adjunct professor and senior research fellow Joseph Hickman, a former Guantanamo guard who challenged the military's narrative surrounding the June 2006 deaths of three detainees - the government called them suicides, Hickman came to believe they were murders - makes a much stronger case. The report relies exclusively on internal government and military documents and statements public officials have made since Guantanamo opened 13 years ago to show how the detention facility "was covertly transformed into a secret interrogation base designed to foster intelligence's curiosity on the effects of torture and the limits of the human spirit."

"Although the government continues to mislead the public by touting that [Guantanamo] houses the 'worst of the worst,' the facts revealed by the Center unveil a different, more disturbing story," the report says, adding that Guantanamo "served as the heart of worldwide interrogation testing and training."

"America's Battle Lab tells the grim story of the most secret aspect of Guantanamo and the Global War on Terror," Mark Denbeaux, the director of Seton Hall's Center for Policy & Research, told VICE News. Denbeaux previously worked with Hickman on a report about the three detainee suicides. He said it was during the course of that investigation when he realized that Guantanamo "was not a detention facility, but a laboratory for intelligence operations."

"Perhaps even more shocking than the idea of human experimentation in Guantanamo was the discovery that two different generals described Guantanamo as America's battle laboratory," Denbeaux said. "One general stated under oath that he received his... orders directly from the president of the United States. The generals did not appear to believe that there was any reason to be ashamed of America's Battle Lab."

The report traces the creation of the "battle lab" to the establishment of a single task force - Joint Task Force-170 - whose primary mission was to conduct interrogations. The report notes that after Guantanamo opened on January 11, 2002, the Joint Chiefs tapped Army Colonel John Custer, who was the assistant commandant of the US Army Intelligence Center and School at Ft. Huachuca, Arizona, to undertake a study of how to obtain intelligence from detainees. Custer's study referred to Guantanamo as "America's Battle Lab." He proposed combining psychological aspects the military and federal law enforcement used during interrogations that would be "conducive to extracting information by exploiting detainees' vulnerabilities."

"[Guantanamo] existed as a place where [intelligence personnel] could push nearly all of the boundaries of torture without fear of liability," the report says. "It placed the intelligence mission at the forefront, demoting any interests of the detention mission. In doing so, the laboratory was formed, paving the way for a multitude of psychological experiments against detainees who were admittedly not 'the worst of the worst,' but were in fact merely 'low-level enemy combatants.' [Guantanamo] operated as a Battle Lab, a world where experimentation on the defenseless served to generate data with which to counsel and train interrogators at military facilities across the globe."

Bush administration officials have long disputed such characterizations, and have said any mistreatment of detainees was the work of a "few bad apples." However, one former top military official told the Armed Services Committee that Guantanamo was described to him a "battle lab." Army Colonel Britt Mallow, the commander of the Criminal Investigative Task Force, said Guantanamo officials Major General Mike Dunleavy and Major General Geoffrey Miller used the term "battle lab," meaning "interrogations and other procedures there were to some degree experimental, and their lessons would benefit [the Department of Defense] in other places."

Additionally, the deputy commander of the Criminal Investigative Task Force told Senate Armed Services Committee investigators, "there were many risks associated with this concept... and the perception that detainees were used for some 'experimentation' of new unproven techniques had negative connotations."

The Seton Hall report says the US paid an enormous price for the way in which Guantanamo was operated. President Barack Obama, who promised six years ago to shutter the detention facility, said the detention facility had become the number one "recruitment tool" for Muslim extremists.

Today, Guantanamo is operated differently. Detainees are no longer "exploited" for their intelligence value. Although detainees continue to be held indefinitely without charge or trial, a "majority have the ability to walk around and do things with a relative degree of freedom," the commander of the detention facility, Rear Admital Kyle Cozad, told VICE News during a recent interview. "They have the opportunity to recreate together and the opportunity to socialize."

Cozad said he's not responsible for what took place in the past, and neither he nor the personnel who have been deployed to Guantanamo should pay for it.

"I will place my right hand on a Bible and attest to the fact that everything we do here complies with the Geneva Convention, Common Article 3, and it's safe and humane," he said.

Hickman, the former Guantanamo guard, believes Guantanamo ceased being a "battle lab" when Obama was sworn into office in 2009. But he still thinks detainees are abused.

"I think Guantanamo is still operated with the same mentality as it was in the past when it was a battle lab," Hickman said in an interview with VICE News. "Many of the [standard operating procedures] that were in place to support intelligence operations when it was a battle lab are still in place today. For those reasons, I believe Gitmo today is an environment of mistreatment and abuse."