The hills of southern California are covered in wildfire, stretching some 160,000 acres this week. Under the tax bill that recently passed the House of Representatives, those whose homes have been destroyed would potentially take another hit come tax filing season.

That’s because tucked into the 450-page bill is a provision eliminating the ability of filers to deduct personal casualty and theft losses resulting from natural disasters not covered by insurance, save those that apply to victims of Hurricanes Harvey, Irma and Maria.

The provision was included as a means of raising money to offset some of the tax cuts elsewhere in the bill. Democratic aides told The Daily Beast it was not entirely clear how much would be raised by eliminating the deduction, though they suspect it would be in the billions considering the scope of those potentially affected. A spokesman for House Ways and Means acknowledged that the bill would only carve out deductions related to the three major hurricanes of 2017 but added that "Chairman [Kevin] Brady looks forward to working together in conference to reconcile these similar proposals. At the same time, the Chairman continues to work with Members who have introduced legislation that will provide tax relief to families affected by the recent wildfires in California.”

Tax experts told The Daily Beast that those impacted by California wildfires may be able to deduct their property losses if they filed before the end of the year. But the likelihood that those fires will persist—and the certainty that future natural disasters will take place—makes the reform deeply consequential; certainly compared to the scant news coverage it has received.

“There have frequently been special provisions added to aid federal disaster victims, but the casualty loss deduction has been around a long time without any of these kinds of constraints,” Michael J. Graetz, Columbia Alumni Professor of Tax Law told The Daily Beast.

The Senate version of the tax bill is more generous. The deduction for personal casualty and theft losses resulting from natural disasters is, likewise, eliminated but not in cases of presidentially-declared disasters. President Donald Trump has declared a state of emergency in California, which, as NBC reported, is separate from a major disaster declaration

“There must be a declaration of a disaster to take the deduction,” Michael Knoll, co-director for the Center for Tax Law and Policy at the University of Pennsylvania Law School told The Daily Beast. “However, I believe those amendments have an effective date of January 1, 2018.”

Under the Senate bill, as one Democratic aide noted, if your house burnt down in a fire and the president didn’t declare it a natural disaster, you would not be able to take a deduction. Ultimately, the two chambers will have to hash out the differences between their two bills in conference committee. And where they end up could have massive ramifications for natural disaster victims going forward.

Already, some of the GOP’s California delegation are voicing concern about the potential ramifications of these bills for constituents in the state.

“Congress must approve and provide tax relief to victims of the California wildfires,” Rep. Ken Calvert (R-CA) told the Los Angeles Daily News . “We could do this broadly in the larger tax package or in a more targeted manner as stand-alone legislation.”

But it’s not clear whether tax writers can afford to scrap the revenue produced by eliminating the deduction. Instead, the expectation is that they will settle on the Senate’s version. If that does, indeed, end up being the case it would grant an immense amount of fiscal influence to each natural disaster declaration a president makes—and likely result in him or her making far more declations. That said, Graetz wasn’t too clear if the current White House occupant would be so generous.

“Given the way this tax bill is treating Blue state voters, perhaps the president will declare federal disasters going forward only in Red states,” he said.