The United States Court of Appeals for the Ninth Circuit has, at least temporarily, struck down a ban on gas hookups in new buildings in Berkeley, California, a ruling that could have significant implications for New York state’s looming ban on gas in new building construction, as well as bans imposed by New York City and other cities in the state.

The purpose of these bans is to constrain, and eventually eliminate, the use of natural gas in residential and commercial buildings, in order to reduce greenhouse gas emissions, especially methane, a more potent greenhouse gas than carbon dioxide.

The ruling is a setback to those efforts. If federal courts with jurisdiction over New York follow the Ninth Circuit’s lead, they will make it much harder to achieve the greenhouse gas emissions reductions mandated by the state’s Climate Leadership and Community Protection Act.

But supporters of gas appliances shouldn’t get too excited.

When Berkeley banned gas hookups in new buildings, the California Restaurant Association (CRA) challenged the ordinance in federal District Court. Overwhelmingly restaurants use gas stoves because they cook hotter than electric stoves and the heat level is more readily controllable. The CRA claimed that one or more of its members would be harmed by the inability to use gas for commercial cooking.

The Federal District Court ruled against the CRA, which then appealed to the Ninth Circuit, where — as is the norm — the case was heard by a panel of three judges.

The crucial legal question is arcane, relating to the application of U.S. Department of Energy standards for energy use in appliances. First created in response to the 1973 energy crisis, these standards are intended to be minimum standards applicable across the country, so they preempt the creation of stricter standards by state and local governments.

The language the panel had to interpret is: “no State regulation concerning the energy efficiency, energy use, or water use of such covered product shall be effective with respect to such product.”

It comes down to what the word “concerning” means.

By one reading, this would mean only standards that that operate directly on the covered products themselves. Berkeley clearly could not, for example, have required restaurants using gas stoves to use ones that are more efficient than the federal standard. But the city’s argument is that banning gas-piping in new buildings does not regulate the efficiency or energy use of any appliance — it regulates only the availability of fuel for appliances. If an appliance cannot receive the necessary fuel, the appliance simply won’t be used, and so its amount of energy used is not the subject of the regulation.

The CRA argued for a broader reading, where any regulation that controlled the use of fuel in appliances would be preempted by the federal standard. Any effective ban on the use of the appliances, it argued, is a regulation of appliance efficiency.

Siding with the CRA, the panel wrote in its opinion that the “EPCA defines ‘energy use’ as ‘the quantity of energy directly consumed by a consumer product at point of use.’” And “a regulation that prohibits consumers from using appliances necessarily impacts the “quantity of energy directly consumed by at point of use.”

If the ruling holds up, it would technically apply only in the Ninth Circuit (essentially the West Coast) but could provide a strong foundation for a challenge to gas bans in New York, both at the city and the state level.

But restaurateurs and gas appliance enthusiasts should view this decision with constrained enthusiasm. Berkeley’s next step will surely be to ask for a rehearing of the case en banc, meaning that all of the judges of the Ninth Circuit could rehear the case and rule on it. The Court doesn’t have to grant such a request, but they may consider this issue important enough to do so.

The three judges on the panel also are all Republican appointees, who are likely more conservative than the Ninth Circuit as a whole, which famously has been known as the country’s most liberal circuit.

The politics of environmentalism ideally should not be a determining factor in the judges’ decisions, but it cannot be ruled out. The issue should turn wholly on the proper interpretation of the text of the EPCA, but a judge’s political leanings can influence their textual interpretations, even if just subconsciously.

And despite the panel’s claim that theirs is the “plain reading,” Berkeley’s ordinance is far enough removed from what the Department of Energy was contemplating when they wrote the rule that it all remains open to interpretation. It’s not at all obvious that the text shouldn’t be read to apply only to regulation of the efficiency of the appliances themselves rather than to whether fuel can be supplied to them.

Whatever the outcome, the losing side could then appeal to the U.S. Supreme Court. But the Supremes take only about one percent of the cases that are appealed, so for either side that would be a long shot. One factor that could potentially persuade the Supreme Court to take the case is if New York’s impending ban on gas hookups is challenged, and federal courts there come to a different conclusion than the Ninth Circuit. In that case federal law would be applied differently in different parts of the country, a conflict the Supreme Court often seeks to resolve.

In the end, the Ninth Circuit panel’s ruling in CRA v. Berkeley, while a tactical win for gas users, is but one battle in a much longer strategic conflict.