It was just announced that Prince George’s County is considering implementing a $.25 per ride surcharge on all transportation network company (TNC) facilitated trips originating in the county. The surcharge, which is allowed as part of this year’s so-called “Uber law”, would be used to fund expanded bus service in the county and increase the number of cabs equipped to serve people with disabilities.

While the tax would be legal, it would certainly be a burden on the county’s TNC users. An extra quarter a ride doesn’t sound like much, but rising ride volumes could make it a lucrative revenue source for the county. Funding local government through excise taxes is a risky endeavor, as they can vary notably between years, making financial planning a challenge, and sometimes leaving budget holes which are a challenge to fill.

The case could be made for using the revenues for extra disabled-accessible cabs if it frees the companies from potential requirements to operate their own fleets of vehicles for disabled service. Using TNC surcharge revenues to pay for expanded bus service would be different and wholly unwise. Transit service needs a stable revenue stream if it is to be provided. An excise tax on new and ever-changing companies like TNCs does not provide that.

Moreover, the logic behind using the surcharge for bus service is unclear. Why would the county want to shift riders from unsubsidized TNCs to county-subsidized buses? The claim is that the goal is to expand bus coverage, which usually means the goal is to provide transportation options to the poor. Yet a recent study by the Manhattan Institute’s Jared Meyer found that TNC service popular and growing in New York’s poor and minority-dominated neighborhoods. If anything, the surcharge would make TNCs more expensive, forcing more riders onto unpredictable and inconvenient bus service.

While Prince George’s county is certainly allowed to levy this surcharge on TNC companies, it would be unwise to attempt to rely on them to back any kind of new public spending.