In the Bleachers by Ben Zaehringer for May 29, 2015

This was in Ripley’s Believe It Or Not and Snopes confirms it.

“It isn’t often we have occasion to employ the term “accidental self-defenestration” in an article, but that phrase certainly applies to the case of Garry Hoy, a 38-year-old lawyer with the Toronto law firm of Holden Day Wilson, who on 9 July 1993 plunged to his death from the 24th floor of the Toronto-Dominion Bank Tower building at TD Centre in front of several horrified witnesses.

For motivations that remain unclear to this day Hoy had apparently developed a fondness for showing off the tensile strength of office building windows (and/or demonstrating his fearless trust in that aspect of building design) by running and hurling himself at window panes in front of onlookers, who would watch a stunt that always ended with Hoy’s bouncing off of the window panes, leaving both glass and lawyer unharmed. On a fateful day in 1993, however, Hoy attempted his feat in front of a group of prospective legal apprentices with disastrous results: Apparently the first attempt came off as usual with Hoy harmlessly rebounding off the window, but when Hoy threw himself against the pane a second time, it popped out of its frame and sent Hoy fatally tumbling 24 stories to the courtyard below."

http://www.snopes.com/horrors/freakish/window.asp