The bill amends the 1899 Local Act 437, which pertains to the incorporation of the City of Mackinac Island in Mackinac County, Michigan. It introduces new legal language that grants the city additional general powers, particularly in Chapter IX, allowing the city council to enact ordinances related to public order, health, and safety. Notable insertions include the authority to regulate and license all aspects of ferry services, including fees for baggage, early boarding, and vehicle parking, as well as the ability to impose penalties for violations of these regulations.

Additionally, the bill outlines a referendum process, requiring approval from a majority of the city's electors for the amendments to take effect. The question of approval will be presented to voters at the next regular election or a special election called for that purpose. If the majority votes in favor, the amendments will take effect ten days after the election results are certified.