Privacy concerns aren’t getting the attention they deserve. Travel datasets have proven to be particularly susceptible to privacy breaches through re-identification attacks that target these sparse datasets. Researchers have been easily able to identify individuals in open datasets of anonymized:
- taxi trajectories in New York City,
- bike-sharing trips in London and
- subway data in Riga2.
In another example from a recent news story, the Pillar obtained commercially available location data and correlated it with data on a Roman Catholic Monsignor’s phone. They thereby revealed he had visited gay bars and private residences while using Grindr, a dating app popular with gay people. Statistically speaking, travel patterns are more unique than fingerprints. Any data engineer “worth their salt” can launch a reconstruction attack on a sparse dataset in minutes. On data privacy grounds alone, VMT is a nightmare waiting to unfold.
Meanwhile, policy makers are ignoring an even bigger hurdle: VMT is a bad idea, to begin with, because it will worsen inequality. Let’s examine why. As a nation, we’ve underinvested in infrastructure AND mass transit for decades. Mass transit hasn’t kept up with the redistribution of the population into suburbs, or the move of jobs into business parks. Much of the nation’s workforce commutes by car. For many, there isn’t a practical alternative. Charging a VMT fee will disproportionally harm the 40 million American workers earning minimum wage. It’s hard to see how this fits with the White House’s recent announcement of a shift in regulatory priorities in favor of social welfare and equity.
Besides, in many cities commuters already pay a fee for vehicle miles traveled. From Singapore to Sydney to Washington DC, toll roads are so common that few commuters have a practical alternative if they want to get to work on time. As if that isn’t bad enough, toll road operators have also introduced Express routes that permit higher speeds for higher prices. Express toll roads function as a kind of line-cutting privilege for those ready, willing, and able to pay the price. They disproportionately benefit the affluent by providing them with that scarcest of commodities – time. And they disproportionately penalize the less well-off. Adding a VMT tax will heap insult on top of injury.
Let’s take a wider view of the situation. Since the 1980’s Congress has split federal transportation funds 80% for highways vs. 20% for transit. While carbon emissions from new vehicles have declined in the same period, there are still many older, carbon-spewing vehicles on the road. Trucks, overwhelmingly users of diesel fuel, are particularly culpable. The transportation sector accounted for 29 percent of greenhouse gas emissions in 20193, the largest share of any industry. Simply put, highway funding contributes to global warming which is an existential threat to our species. Reductions in highway funding are an important way to tackle climate change. It’s time to rebalance America’s highway and transit policies.
82.66% of the US population lives in cities and suburban areas4. These areas are heavily dependent on public transportation. Unfortunately, after 4+ decades of underinvestment, urban areas are also underserved by transit services. Low-income workers are particularly dependent on mass transit for their commute. The lack of reliable transit in the U.S. means low-income Americans spend ~30% of their household income on transportation to get where they need to go, compared to 13% on average for all Americans. It’s time to invest in cleaner, zero-emissions buses and metro services. Such investment will create opportunities for historically underserved communities to make greater contributions to the economy, and enjoy the benefits thereof.
It’s long past time for Congress to flip the split to 80% on transit and 20% on highways. Even then, we still have to address the privacy and ‘double taxation’ issues of VMT. At Definitive Logic, one of our Credo Principles is “treat others how you want to be treated”. We wouldn’t want to be subjected to double taxation and privacy threats. We reject the proposed VMT.
1 https://www.nature.com/articles/s41467-019-10933-3; and https://www.cs.utexas.edu/~shmat/shmat_oak08netflix.pdf
2 Navigating Speed Bumps to a Possible Federal Vehicle Miles Traveled Fee | RAND