Gen. Baccus of the Rhode Island National Guard was sent to the Naval base at Guantanamo to take charge of detention operations from March to October 2002. In this interview, he describes the stresses of working in such a high-security environment and what he calls a "necessary tension" between military intelligence (MI) and military police (MP). "[MIs] have to work their relationships to try and garner information. Our issue is more security of the camp, the detainees, how the military police and the detainees operate together every day. … At times, they may not necessarily go in the same direction."

Berenson was associate White House counsel to President Bush from January 2001 to January 2003. Now an attorney in private practice in Washington, Berenson talks about how the need for "forward-leaning" thinking that emerged in the days and months after the 9/11 attacks drove the president's advisers to give him as much power as possible to prevent other attacks. "Everybody had to assume at that time that further attacks or perhaps even worse, were planned," he explains. "And all of us were concerned with ensuring that the president had the full complement of tools and weapons at his disposal that came with his office. …" Berenson, like John Yoo and some other lawyers advising the president, was a member of the Federalist Society and had clerked for U.S. Appeals Court Judge Lawrence H. Silberman.

Lt. Col. Thomas Berg was an assistant federal public defender and Army reservist when he was called up after 9/11. He was invited to participate in a Defense Department project to set up war crimes tribunals for captured Al Qaeda and Taliban prisoners. Here, he explains how the process they established for the tribunals, based on the Uniform Code of Military Justice and the Geneva Conventions, was rejected by the Pentagon civilian leadership. "They were overly result-oriented, terrified that somebody might be acquitted in the process," he tells FRONTLINE. Berg then traveled to Guantanamo to serve as a Judge Advocate General (JAG), or military legal adviser, to Gen. Rick Baccus, who headed detentions there until October 2002. He describes how confusion on the ground over the rules for detention and intelligence gathering led to bitter fights between the military police and intelligence personnel at Gitmo.

Sgt. Roger Brokaw (Ret.) came to Iraq as an interrogator in the late spring of 2003. He worked at Abu Ghraib for six months and estimates that only about 2 percent of the people he talked to were dangerous or insurgents. "The police were bringing people in because they had grudges against somebody or didn't like somebody. … So they'd tell us, 'You know, this guy's a terrorist,'" he says. According to Brokaw, the attitude among Americans in Iraq was that everyone they saw was a terrorist. "So when they went into interrogate these people, they already had this mindset," he explains. He says he saw detainees arrive at Abu Ghraib looking like they'd been beaten up: "I saw black eyes and fat lips, and some of them had to be treated for different bad abrasions on legs and arms, cuts."

An FBI special agent from 1977 to 2002, Cloonan started working Al Qaeda cases in the mid-1990s. In this interview, he explains why he believes the FBI's method of interrogation is successful. He describes how the FBI cultivated former Al Qaeda operatives Jamal al-Fadl and Ali Mohammed as cooperative sources in the years before 9/11. Cloonan also recounts the FBI's battle with the CIA over custody of Ibn al-Sheikh al-Libi, who ran an Al Qaeda training camp in Afghanistan and who was one of the highest-ranking Al Qaeda operatives captured in the first months of the war in Afghanistan. Cloonan says al-Libi was revealing information that could have been useful in the prosecutions of Richard Reid and Zacarias Moussaoui, before he was transferred to CIA custody, duct-taped, put in the back of a truck, and sent to Egypt for more aggressive interrogation. Cloonan also discusses the FBI's role at Guantanamo and why he believes little good intelligence came out of there.

Danner has written widely on the moral and political implications of using torture to obtain information. He has published numerous articles in The New York Review of Books and is the author of Torture and Truth: America, Abu Ghraib and the War on Terror. Here, he describes the paper trail of memos and documents that show how interrogation policies were changed in the aftermath of 9/11. "I think no one assumes that the American intelligence agencies have never tortured captives or prisoners in their history," he says. "What probably is very new, and new with the war on terror, is that there exists now documentary evidence, including documents from the Department of Justice lawyers themselves, talking about these procedures and in effect, approving them." Danner says that these memos were driven not only by the need to quickly obtain actionable intelligence, but also by an ideological belief in the "untrammeled notion of executive power." He tells FRONTLINE that if Americans read the investigations into the abuses at Guantanamo and Abu Ghraib -- which he describes as "a fascinating exercise in bureaucratic damage control" -- they would learn that "… the abuse was much more thoroughgoing and systematic than they had been led to believe."

Jacobson worked on policy planning in the Office of the Secretary of Defense, where he helped develop the detention policies at Guantanamo. In this interview, he explains why declaring Al Qaeda and the Taliban "unlawful enemy combatants" was a mistake. He also talks about the confusion over what interrogation techniques were allowed and describes it as symptomatic of larger problems with United States policy. "The problem is not so much how the detainees have been treated, how the detainees have been interrogated," Jacobson says. "There's certainly a perception problem there, but the problem was the broader detention policy issue. What is the written policy of the United States government? What is our goal? How are we going to treat captured terrorists? I don't think there still is a clear policy. Some are tried in federal court, some are locked up in the brig in Charleston, S.C., and some are at Guantanamo, and there's no consistency. Clearly, this was ad hoc from the beginning."

A Gulf War veteran and Army reservist, Karpinski served as Brigadier General in charge of the 800th Military Police Brigade in Iraq, where she supervised detention operations at Abu Ghraib and elsewhere. She was in command of Abu Ghraib when the abuses began there. As a result of the Army's investigation into the prison abuse scandal, Karpinski was given a letter of reprimand, relieved of her command, and demoted to colonel. To date, she is the most senior officer to be punished in the scandal. In this interview, Karpinski describes how as the insurgency in Iraq escalated, the military was pressured to produce actionable intelligence. She recounts a visit from a team from Guantanamo, headed by Maj. Gen. Geoffrey Miller, and says Gen. Miller told her, "We're going to change the nature of interrogation out of Abu Ghraib." Karpinski suggests that the individuals court-martialed in the Abu Ghraib prison abuse did not come up with the tactics seen in the notorious photographs on their own. "I know, with no doubt, that these soldiers didn't wake up that morning and say: 'Hey, let's go screw with some prisoners tonight,'" she tells FRONTLINE. "… Lynndie England surely did not show up in Iraq with a dog collar and a dog leash."

Gen. Jack Keane (Ret.) served in the U.S. Army for 37 years and was the Army's vice chief of staff from 1999 to 2003. In the summer of 2002, Defense Department officials, unhappy with the quality of intelligence they were getting from Guantanamo, sent Gen. Keane to conduct an assessment. He tells FRONTLINE that he learned that the military intelligence and military police on the base were not working well together, and he recommended bringing in a single commander to unify the two. His recommendation was accepted, and the assignment was given to Gen. Geoffrey Miller. "When Gen. Miller got introduced to Guantanamo Bay, everything just seemed to move into the plus category from the time he got there," Keane says. "Everyone that went down there to look at it saw improvement. …"

Spc. Tony Lagouranis (Ret.) was a U.S. Army interrogator from 2001 to 2005, and served a tour of duty in Iraq from January 2004 to January 2005. He was first stationed at Abu Ghraib; in the spring he joined a special intelligence gathering task force that moved among detention facilities around the country. Here, he talks about how he found a "culture of abuse" permeating interrogations throughout Iraq. "The worst stuff I saw was from the detaining units who would torture people in their homes," he tells FRONTLINE. "… They would smash people's feet with the back of an axe-head. They would break bones, ribs, you know. That was serious stuff." He says he sent reports of the abuse he saw up the chain of command, but he does not believe his claims were followed up on. Lagouranis also talks about the confusion on the ground over whether Iraqi prisoners were subject to the Geneva Conventions. "I mean, there's just no way that what we were doing and what was sanctioned by the Pentagon through the IRE, the interrogation rules of engagement -- there's no way that fit in within the Geneva Conventions," he says. And he describes his own use of military working dogs to intimidate prisoners.

Ratner is a human rights lawyer and president of the Center for Constitutional Rights. He argues that the Bush administration's actions in the war on terror have rejected 200 years of constitutional rights. "The idea that you can simply imprison someone indefinitely without a trial, without any access to attorneys, incommunicado in a place outside the law, Guantanamo, should be anathema to all of us," he says. "That's the beginning of the end of rule of law in the United States." He is the lawyer for a group of British detainees known as the "Tipton Three." Here, he tells the story of how these men were transferred from Afghanistan to Guantanamo. U.S. intelligence believed it had seen the three men in a video of Osama bin Laden at an Al Qaeda training camp; after a year and a half of coercive interrogation, the men admitted to being at the camp. But the British government later found information revealing the men had been in Britain at the time they were supposedly at the training camp and they were released. Ratner says his clients' story proved to him that "the way people were picked up in Afghanistan and in Pakistan was relatively arbitrary. You didn't pick up the worst of the worst or the most dangerous."

Scheuer was a CIA agent who worked on national security issues related to Islamic extremism from 1985 until his retirement in 2004. He formed the CIA unit responsible for trying to capture Osama bin Laden and headed it from December 1995 to June 1999. Scheuer was also involved in setting up the CIA's rendition program in which terrorist suspects are taken to a third country for interrogation. Critics argue that rendition is "outsourcing torture," but Scheuer defends the program. He says the primary point was to get terrorist suspects who were planning an imminent attack on U.S. interests off the streets and to incarcerate them in a country willing to accept them. Those countries had to provide the U.S. with a guarantee that the suspects would be treated lawfully. "I worked in covert action for 20 years, and there was no covert action program I was involved in that was ever more scrutinized by lawyers," he says. Here, Scheuer also describes the CIA's perspective in its turf battles with the FBI over what to do with captured terrorist suspect Ibn al-Sheikh al-Libi. "I think you have to decide what's in the best interest of America," he says. "… Why bother putting him through the court system in the United States when you might be able to save American lives by using him in another manner?"

Yoo was a deputy assistant attorney general at the Justice Department's Office of Legal Counsel from 2001 to 2003. A 1992 graduate of Yale Law School, Yoo joined the Federalist Society, a national group of conservative and libertarian lawyers, while still a student. He clerked for U.S. Appeals Court Judge Lawrence H. Silberman, a federal judge much admired by the right, and then for U.S. Supreme Court Justice Clarence Thomas. An expert in war powers, Yoo was the principal author of Justice Department memos giving President Bush extraordinary power to prosecute the global war on terror, ignoring the Geneva Conventions regarding captured terrorist suspects and placing a high bar on what constitutes torture. He tells FRONTLINE that the logic behind these decisions flowed from two basic questions about the 9/11 attacks: Was the U.S. at war? And should Al Qaeda be treated the same as a nation-state? Now a law professor at the University of California, Berkeley, Yoo defends his controversial advice: "The one thing I think we don't want is for the government to be hamstrung in the way it interrogates people who have knowledge of pending attacks on the United States because we have so much disagreement about what those phrases mean that we can't do anything. So I think it's important that the government do figure out what that language means and how to apply it, rather than operating [in] this sort of vague fog of uncertainty."