To encourage minority business and foster pride in minority heritage, a state adopted legislation exempting magazines and other periodicals from the state's receipts tax if 20% of the magazine is devoted to articles concerning minorities (a commission was set up to sample magazines to determine on a yearly basis whether they should be exempt). A publisher produced a sports magazine in the state that occasionally contained articles about minority athletes, but the commission determined that the publisher's magazine was not eligible for the receipts tax exemption. After paying the tax assessed on her magazine, the publisher sued for a refund. How will the court most likely rule