But this lawsuit – and the city's bypassing of a review process, and the buses themselves – isn't really about the environment. It's about class, and it could foretell big changes for how California's cities grow in the future.

Activists filed suit against San Francisco and its transit agency for violation of the 1970 California Environmental Quality Act (CEQA), claiming that an environmental review of the tech shuttles' impact on the city is necessary. (The city had skipped an environmental review of the bus program in its haste to resolve a painful political issue.) A CEQA lawsuit is a powerful procedural weapon in activists' fight against more than just the buses. They are also appealing the city's decision on the basis of residential displacement, as research has shown a strong correlation between the tech bus routes and rising housing costs.

But if that sounds like an unusual take on environmental impact, it is – and it's brand-new.

Last fall, CEQA was updated in an effort to promote more dense, so-called "smart growth" in California's cities. The old law prohibited the environmental judgment of a project based on socio-economic factors, and only considered "displacement" in any case in which houses would be knocked down and new ones would have to be built. But the new law calls for the state to write a set of review standards by which to judge developments that might destabilize neighborhoods and push out poor and middle-class residents.

This is the first high-profile lawsuit to appeal on the basis of displacement – and those state standards are still on the drawing board and there's no case law to go on.

Gentrification does have environmental ripple effects. Dense city living is better for the environment, but given private conveniences, it's becoming the exclusive realm of the rich. So, when San Francisco workers are forced to move out to cheap suburbs without mass transit, they become reluctant urban drivers – by some standards, more eco-evil than Google. The burden and the blame for urban pollution then often falls on the poor, who can't afford the well-funded environmental measures of Google and Genentech.

But environmental stability in an age of climate change doesn't just mean running buses instead of driving alone. Building and maintaining a resilient social infrastructure is arguably just as vital to surviving future crises as building flood-proof parks. It's often neighborhood relationships "that might make the difference between life and death" in disasters, sociologist Eric Klinenberg told NPR.

Located on a volatile fault line and surrounded on three sides by rising sea levels, San Francisco is always planning for crisis. But as high rents and private transit tear up neighborhoods, city disaster networks will have to fill in for those broken relationships.

It's clear that the buses absolutely play a role in reshaping San Francisco's neighborhoods. One study found that, without shuttle access, nearly two-thirds of city-dwelling respondents said they would drive instead – and about 40% would move closer to work for convenience. Tech companies and San Francisco transit officials have argued that the buses are needed to take those hypothetical thousands of cars off the road each day. Google in particular promotes its eco-friendly company ethos and clean-running shuttles.

The old CEQA measures impact on roads by looking at traffic congestion, so projects that slow cars down – like bike lanes – often show a "negative" environmental impact. The new CEQA standards measure projects based on vehicle miles traveled. Depending on the details of model used to determine the impact, tech shuttles could be deemed positive under either standard, even if it means more diesel exhaust for San Francisco neighborhoods.

And either way, the law is often used more for political means than environmental ones.

San Francisco tries to scuttle environmental reports all the time, and activists constantly sue them for it, so, in a certain sense, this is business as usual. But if this group can make their case against the company shuttles, they might not just force a city drunk on the promise of technology to take stock of its values – they might impact development across the entire Golden State.