The sponsor of a measure that would give local governments the ability to tack on a municipal gas tax on top of state and federal gas taxes said it was designed to level the playing field inside the state’s boundaries, but a group representing convenience stores said it would make Illinois even more of an outlier compared to neighboring states.

Senate Bill 2978, filed earlier this month, would open up the ability for all municipal governments to tack on an extra 3 percent gas tax to the state and federal gas tax.