You're probably wondering if the revenue generated from the proposed gas tax bill, which would increase gas taxes and add fees to pay for road infrastructure over the next decade, can only be used for transportation. 

Here's what we found out:

1. Gas taxes

This tax revenue is already protected by the state Constitution. The state's Finance Department told us that "there has to be a transportation nexus or connection" with these funds, meaning the state could not, for example, use the money for prisons.

Currently, both gas and diesel excise tax revenue goes to the State Transportation Fund to construct and maintain public roads and mass transit. 

Here's where the new gas tax revenue would go:

And here's where the new diesel tax revenue would go:

2. Transportation improvement fee

Revenue from this new fee, based on the value of your vehicle, cannot be used for purposes other than transportation. An amendment to the gas tax bill, SCA 2, states that the state Legislature cannot borrow this money or use it for other purposes. The money also cannot be used to repay bonds unless voters approve this change in the future. 

Here's where the new transportation improvement fee revenue would go:

3. Zero-emission vehicle registration fee ($100 for model years 2020 and later):

According to the bill's language, revenue from the zero-emission vehicle registration fee would go to the State Transportation Fund. 

In general, vehicle registration fees are also protected by the state Constitution, but not all of it is transportation-related. This revenue goes to the Motor Vehicle Account. 

From each fee, $24 goes to the California Highway Patrol. The rest of the fee supports the DMV and other state agencies. 

Here's where the new zero-emission fee revenue would go: