Investigative journalism, like democracy and love, comes down to the question of whom to trust. Except when you have the listening device under the Mafioso’s desk or the hidden camera in the dirty restaurant kitchen, there’s always an element of, “you finds your source, you takes your chances.” Few times in my career has this dilemma been driven home more clearly than in our report on alleged abuse of detainees in Guantánamo Bay.

My weekly news-magazine program on HDNet, Dan Rather Reports, got the first American television interview with Lakhdar Boumediene, the latest detainee to leave Guantánamo. It was Boumediene’s own Supreme Court case that gave Guantánamo detainees the right to habeas corpus review. A district court judge, who had been appointed by President Bush, reviewed secret evidence and found that the government’s sole reason for bringing Boumediene to Guantánamo was the report of a single, uncorroborated, unidentified source. The court ordered Boumediene released and finally, after six months of legal limbo, the French government agreed to resettle him.

Dan Rather interviews Lakhdar Boumediene, a man who spent nearly seven years in the U.S. detention camp at Guantánamo Bay.

The conundrum of a story told primarily through dueling interviews (we also spent extensive time at Guantánamo with the admiral in charge) is so much on my mind because its implications in this particular case are so weighty. Boumediene’s claims about what went on in the few years after the 9/11 attacks would, if true, belie the central argument of those who defend the camp’s harsh early days. Furthermore, his claims about ongoing abuse at the hands of guards would—again, if true—lay to waste the message of reform and humane treatment the Pentagon and the Obama administration have worked so hard to create.

Boumediene described individual guards and a nurse who were unchecked in their sadism up almost to the day he left the camp, beating him and administering medical procedures in excruciating ways.

Former Vice President Dick Cheney in his famous American Enterprise Institute speech last month condemned those who want to shut Guantánamo down because of supposed abuse. He accused them of “a strange and sometimes willful attempt to conflate what happened at Abu Ghraib prison with the top-secret program of enhanced interrogations.” “It takes,” he wrote, “a deeply unfair cast of mind to equate the disgraces of Abu Ghraib with the lawful, skillful, and entirely honorable work of CIA personnel trained to deal with a few malevolent men.” Clearly, Boumediene’s tales of sexual humiliation and physical abuse at the hands of interrogators and military doctors—not just a few guards—would demonstrate that cruelty bordering on what went on at Abu Ghraib was a matter of interrogation policy and not just the deeds of what Cheney called “a few sadistic prison guards.”

Dan Rather visits Guantánamo and interviews Rear Admiral David Thomas.

Similarly, the message, “this is not the Guantánamo of old” has been intense from both the Obama administration and, as we saw when we traveled there a few weeks ago, those in charge of the detention center themselves. We toured the part of the facility meant for cooperative detainees and saw a video library ( Night at the Museum is apparently the most popular title), elliptical machines, and food that I’d be proud to serve guests at my home in New York. Boumediene, however, in his interview, described individual guards and a nurse who were unchecked in their sadism up almost to the day he left the camp, beating him and administering medical procedures in excruciating ways. These episodes, he claims, took place in the areas of Guantánamo Bay—and there are many—that journalists are not allowed to see.

Boumediene comes across as credible and trustworthy. He nonetheless, as a likely innocent man taken off the streets and thrown in a tropical prison thousands of miles away, has some incentive to exaggerate. The admiral we interviewed, who is in charge of everything that goes on in the detention center, also seems earnest and believable—but he, too, has a particular version of what goes on at Guantánamo that suits his purposes. Same for the patient and sympathetic young soldier-guard whom we interviewed about her interactions with the detainees.

So where are we left? The truth about Boumediene’s alleged abuses of 2002-2003 has immense importance for the shape into which the still-molten history of Guantánamo will harden. The truth about his allegations of ongoing abuse has immense implications for what to do about Guantánamo, and how to create a rules and oversight system for whatever system for detaining suspected terrorists will inevitably follow. We as journalists have the luxury of telling both sides of the story and leaving it at that. You have the responsibility to decide.

(Note: Boumediene’s first American interview was conducted in a suburb of Paris on May 28. Dan Rather Reports aired excerpts of the interview on June 2. A full one-hour Dan Rather Reports about Guantánamo and Boumediene—as well as the situation of other detainees—will be aired on HDNet tonight, 8 p.m. Eastern time, and subsequently later in the week.)

Dan Rather is anchor and managing editor of HDNet's Dan Rather Reports. For 24 years, he served as anchor and managing editor of the CBS Evening News with Dan Rather. His books include The American Dream, Deadlines and Datelines, The Camera Never Blinks, and The Palace Guard.