In 1961, the Indiana legislature repealed the 1957 law that made central time official Indiana time, allowing any community to observe daylight saving time. The Interstate Trade Commission divided Indiana between the central time zone and the eastern time zone. Previously, 77 counties, mostly in Indiana, were in the Eastern Time Zone and did not observe daylight saving time. At this time, 82 counties were in the Eastern Time Zone and ten counties were in the Central Time Zone.
While there was much debate about the observance of daylight saving time within the state, the result of this legislation created greater uniformity across the state with respect to the observance of the schedule. Advises the Department of Transportation that any Indiana county that is currently in the central time zone should remain in the central time zone and that Clark, Dearborn, Floyd, Harrison and Ohio counties should remain in the eastern time zone. With this change, 80 counties are in the Eastern Time Zone and 12 Counties are in the Central Time Zone. It states that the state supports the effort of any county to change the time zone in which the county is located according to procedures established by federal law.
Five counties in Clark, Dearborn, Floyd, Harrison and Ohio, which were in the eastern time zone, did observe daylight saving time, and ten other counties, Gibson, Jasper, Lake, LaPorte, Newton, Porter, Posey, Spencer, Vanderburgh and Warrick, which were in the central time zone, observed daylight saving time. Request to the United States Department of Transportation to initiate procedures for holding hearings on the question of the location of the boundary between the eastern time zone and the central time zone in Indiana.