10/18/2009 05:12 am ET Updated Dec 06, 2017

Duty vs. Conscience at Gitmo: A Former 9/11 Prosecutor Speaks Out

Lieutenant Colonel Stuart Couch, a government prosecutor, was more than motivated to convict alleged 9/11 conspirator Mohamedou Ould Slahi. After all, Couch was friends with Michael Horrocks, a co-pilot of one of the jets hijacked on September 11, 2001.

But when Couch gained access to details of Slahi's treatment at the U.S. prison in Guantanamo Bay, he was not only shocked, but offended. Couch says Slahi was tortured.

"I felt like what had been done to Slahi just reprehensible," Couch tells NOW on PBS' David Brancaccio. "For that reason alone, I refused to have any further participation in this case."

In this web-exclusive video from NOW on PBS, Couch shares what he saw and heard at Guantanamo, and talks candidly about his controversial decision.

"We can not compromise our respect for the dignity of every human being, " he tells Brancaccio. "If we compromise that, then al Qaeda has been able to effect more of an impact on this country than they have by drivin' a couple airplanes in the Word Trade Center, or crashing one into the Pentagon. Because they've torn at the very fabric of who we are as Americans."

This weekend on NOW, learn more about the tactic of of "preventative detention," a government plan that may detain suspects indefinitely without trial or even formal charges.