IL HB4123

Amends the Motor Fuel Tax Law to specify that motor fuel tax proceeds may be used only for transportation purposes.

Allocates motor fuel tax revenue to multiple funds including the State Construction Account Fund, State Boating Act Fund ($420,000 monthly), and Grade Crossing Protection Fund ($2,250,000 monthly).

Distributes remaining motor fuel tax funds between the State Construction Account Fund and Road Fund until January 1, 2000 (58.4%), then shifts to 45.6% beginning January 1, 2000.

Apportions motor fuel tax revenues to municipalities based on population, counties based on motor vehicle license fees, and road districts based on township/district road mileage, with specified minimum tax levy requirements for road districts.

Establishes that interest earned on invested motor fuel tax funds must be limited to the same transportation purposes as the principal funds.