Lorraine Kowalski was a 29 year old secretary who was courting Marshall Berlin, heir to the massive I. S. Berlin Press printing conglomerate. At 3:30 in the morning of August 12, 1971, Kowalski returned from a night of bar-hopping on Rush Street to his apartment in the John Hancock Center. According to Marshall, Kowalski was drunk and unhappy about the direction their relationship was headed. He retired to the solace of his bedroom. Around 4:10 a.m., he came out, found her clothes on the floor and the bedroom window shattered. She had jumped nude from the 90th floor window onto the Chestnut side of the building and killed herself.

According to the building's engineer, the windows of the John Hancock Center are made out of two quarter-inch thick panels of glass measuring 54 inches square. They can take 280 pounds of pressure per square foot before breaking. Kowalski weighed on 130 lbs. State's Attorney Edward V. Hanrahan had strucural tests performed on a similar window. When the results of the tests came in he refused to press charges and the investigation was quietly closed.