Massachusetts voters have repealed a law that ties future increases in the state's gasoline tax to inflation.

The indexing provision was part of a 2013 transportation financing law that included a 3-cent increase in the gas tax to 24 cents per gallon to help pay for road and bridge projects.

The ballot question approved Tuesday will not lower the tax but will prevent it from going up automatically in the future as the Consumer Price Index rises. As a result, any increases will have to be voted on by legislators.

Opponents of indexing said automatic hikes amounted to "taxation without representation."

But state transportation officials and other supporters of the law argued that Massachusetts needed a consistent and reliable stream of revenue to help fix its crumbling transportation infrastructure.