Why should women have to pay a tax on tampons and menstrual pads, which are surely more necessity than luxury? Perhaps because we all pay sales taxes on all sorts of goods—food, toilet paper, shoes—that are an integral part of modern life. But according to certain California lawmakers and the state's tax board, the sales tax on menstrual products is sexist and must be abolished.

On Tuesday, the California Board of Equalization—the agency in charge of administering California's sales, use, fuel, and vice taxes—endorsed Assembly Bill 1561, which would make menstrual products exempt from sales tax. The measure is co-sponsored by California Assemblymembers Cristina Garcia (D-Bell Gardens) and Ling Ling Chang (R-Diamond) as a way to "bring more gender equity to California's tax code," according to a press release from Garcia's office.

"Effectively we are being taxed for being born as women," she said. "AB 1561 is about social justice [and] an opportunity to end an outdated tax that uniquely targets women for a function of their body, a function we don't control and can't ignore every month of our adult life."

Currently, five U.S. states—Minnesota, Pennsylvania, New Jersey, Massachusetts, and Maryland— exempt menstrual products from sales tax.

There tend to be two libertarian camps on sales taxes, which can be described reductively as either 1) screw sales tax, because screw all taxes, or 2) sales taxes are a good alternative to income taxes for raising government funds. But I think we can all agree that if sales taxes exist, they should be straightforward and applied equally across broad categories. Randomly selecting certain products for exemption based on the idea that they're more or less essential to daily life than others is just a recipe for complication and special-interest-mongering. (Just look at the arcane patchwork of rules concerning food taxes in California, which leave bureaucrats perpetually arguing over things like whether a frozen sandwich microwaved at a gas station counts as a hot or cold food for tax purposes.)

Garcia and Chang argue that for extremely poor women, buying tampons or pads each month is a severe financial burden which we need to mitigate. But is it more of a burden than buying, say, contact lens? Toothpaste? Toilet paper? At least there are reusable options for menstrual products; you can't reuse toilet paper or toothpaste.

Of course, exempting menstrual products from sales tax is only a stepping stone as far as Garcia is concerned. Her end goal is to "make these essential products free or covered by insurance for women," she said.