Last month, the hand-written Guantánamo diaries of prisoner Mahamedou Ould Slahi began appearing in foreign outlets around the world. The 44-year-old Mauritian national and former resident of Germany, accused of aiding the perpetrators of 9/11, had been held for 12 years without trial. I’d read one German magazine excerpt recounting his torture at the hands of U.S. officials, titled, “We’re Gonna Teach You About Great American Sex.”

Turns out, one of those officials was a decorated Chicago detective named Richard Zuley. And according to a new two-part Guardian investigation, Zuley first perfected his “interrogation technique” on Chicago’s black men and women, some of whom accuse him today of having elicited false confessions under torture. Through Zuley, the must-read investigation connects the dots between police torture of non-white, mostly African-American citizens stateside with that practiced on Muslim men under the War on Terror at Guantánamo.

For more on the roots of Chicago’s police torture saga, start here. This month, disgraced Chicago police commander Jon Burge walked free with his pension after serving 4 1/2 years for lying under oath. Burge is accused of torturing or overseeing the torture of more than 100 African-American men on the city’s South and Westsides throughout the 1970s and 1980s.

Zuley was a Chicago police detective from 1977 to 2007. According to The Guardian, he now works for Chicago’s department of aviation.

(h/t The Guardian)