HB 4183 increases the motor fuel tax rate and expands the types of fuels subject to the tax under Michigan law. It directly affects motor fuel sellers (like gas stations) and consumers through higher costs for gasoline and other taxed fuels. The bill amends Section 8 of the 2000 Motor Fuel Tax Act (MCL 207.1008) to implement these changes, which became law immediately upon approval by the Governor on October 7, 2025.
HB 4951 creates a new tax on marijuana sales to fund state road infrastructure projects. It directly affects marijuana businesses (which pay the tax) and state transportation budgets (which receive the revenue). The key mechanism establishes a dedicated funding stream, redirecting tax revenue from cannabis sales toward repairing and maintaining roads, rather than general state funds. The bill became law immediately upon the Governor's approval on October 7, 2025.
HB 4522 modifies Michigan's vehicle code to require heavy trucks (over 10,000 pounds gross weight) to drive in any lane on freeways with three or more lanes for travel in the same direction, rather than restricting them to the rightmost lanes. This directly affects commercial truck drivers and fleet operators on Michigan freeways. The law specifies exceptions allowing trucks to use the right lane only for left turns, safety reasons, or construction-related lane closures. It also prohibits local governments from creating conflicting lane-use ordinances for these situations.
HB 4349 allows Michigan cities to contract with private companies for the maintenance or improvement of private roads within their boundaries. This change directly affects cities seeking to partner with outside contractors for road work on privately owned streets, removing a prior restriction. The bill amends the Municipal Home Rule Act (MCL 117.1-117.38) by adding Section 5l, granting cities this new authority. The legislation passed unanimously in the House with immediate effect on September 17, 2025.
HB 4390 expands Michigan's vehicle code to allow testing of oral fluid (such as saliva) for controlled substances, alongside blood, breath, or urine, when determining impairment. It directly affects commercial drivers who refuse chemical tests for controlled substances or alcohol while operating commercial vehicles. The bill adds a new definition of "other bodily fluid" to include oral fluid and creates a process for "preliminary oral fluid analysis" conducted by certified experts at the scene. This change updates existing suspension rules for commercial drivers who refuse testing, ensuring consistent enforcement for controlled substances alongside alcohol. The policy change specifically targets commercial motor vehicle operators who decline chemical tests for drugs or alcohol.
HB 4391 expands Michigan's vehicle code to allow law enforcement to test for intoxication using other bodily fluids beyond blood or breath, such as urine or saliva. It directly affects drivers suspected of operating a vehicle while impaired, updating sections 625a, 625c, and 625g of the 1949 Michigan Vehicle Code (MCL 257.625a et seq.). The bill amends existing testing methods to include these additional fluids, providing more flexibility for officers during DUI investigations. The bill passed the Michigan House on July 17, 2025, with immediate effect.
HB 4426 amends Michigan's Motor Carrier Safety Act (MCL 480.12d) to set a minimum age of 21 for drivers transporting hazardous materials requiring placards under federal rules. It maintains the existing 18-year-old minimum for most commercial driving but specifically raises the age requirement for hazardous materials transport. The bill does not change medical waiver or grandfathered driver provisions. This change directly affects commercial drivers operating in Michigan who transport hazardous materials requiring placards.
HB 4214 would have modified Michigan's vehicle code (MCL 257.601b & 257.682) to change the procedures drivers must follow when approaching a school bus displaying yellow flashing lights. The bill directly affected all drivers operating vehicles in Michigan who encounter school buses with yellow lights, which typically indicate the bus is preparing to stop for loading/unloading children. It aimed to adjust the specific actions drivers must take during this phase of bus operation. The bill was defeated in the legislature on June 26, 2025, with a vote of 52-51.
SB 235 creates a corporate income tax credit for businesses that use sustainable aviation fuel (SAF). It directly affects airlines and fuel producers in Michigan by reducing their state tax liability based on the volume of SAF they utilize. The bill amends Michigan's tax code (MCL 206.1-206.847) to add a specific provision allowing corporations to claim this credit. This provides a financial incentive for adopting SAF, aiming to support cleaner aviation fuel adoption without specifying environmental outcomes.
SB 217 increases penalties for drivers who commit moving violations (like speeding or reckless driving) that cause physical injury or death to pedestrians, cyclists, or other vulnerable roadway users. It amends Michigan's criminal code (MCL 777.12e) to enhance the penalties for these specific offenses. The bill directly affects drivers whose actions result in harm to non-motorized road users, raising the legal consequences for such incidents.
