Born in 1950 in Chicago, Gary T. Johnson grew up in northwest suburban Park Ridge, Illinois in a politically active family. At the time of the Democratic National Convention, Johnson had recently graduated high school and was a volunteer for Senator Eugene McCarthy's presidential campaign. During the convention, he greeted delegates at O'Hare International Airport and drove them to Chicago hotels. He completed his volunteer activities during the day and went home in the evening. Therefore, he did not participate in any demonstrations or personally experience violence. He recollected how tense the atmosphere was inside the Conrad Hilton Hotel, where McCarthy volunteers worked.