In the late 1990s, Karl developed an interest in the Iroquois Theatre Fire, one of Chicago's great tragedies. Karl researched the history of the fire and the families who were involved, and he created a website to share his information. The website, however, was discontinued in the mid-2010s. Then in 2023, Karl agreed to transfer his body of work regarding the Iroquois Theatre Fire to the Your Next Chapter (YNC) organization. The names and other information from Karl became the building blocks to spawn the Iroquois Theatre Fire Historical Society's website, IroquoisTheatreFire.org.