One day late last November, unit B-2B of the Toronto South Detention Centre was on lockdown. During a lockdown, inmates are placed in pairs in seven-by-16-foot cells for 24 hours a day. The South, as it’s called, is a remand centre for men who are awaiting trial—in other words, they are legally innocent—yet lockdowns are commonplace. This particular one lasted for four days. During that time, the 30 or so inmates on the unit were allowed no access to fresh air, no TV or exercise, and showers and phone calls were limited. The cells reeked of body odour, and the pervading sound, for hours on end, was a mysterious, maddening hum—probably a function of the building’s shoddy acoustics—punctuated by inmates banging on the walls, begging to be let out.