Iowa lawmakers say they’re disappointed the U.S. Supreme Court decided not to hear its second appeal on the way the state taxes casinos. When Iowa’s racetracks sued the state over paying a higher tax rate than the casino boats, the Iowa Supreme Court ruled it violated the state constitution. But the case went on to the U.S. Supreme Court, and about this time last year the nation’s highest court ruled that the two-tiered tax system was legal. The case came back to the Iowa Supreme Court, though, and it disregarded the US Supreme Court ruling and reiterated its original position earlier this year. State Senator Don Redfern says lawmakers asked Iowa’s Attorney General to appeal a second time because the state ruling seemed so “out of whack.” Redfern says a number of lawmakers “have real serious concerns” that the Iowa court’s ruling set a precedent unique to no other state but Iowa, and he hopes it is just an aberration. Legislators say without clarification from the highest court in the land, Iowa’s tax code could come under fire again. This spring the legislature settled the casino tax dispute by approving new rates for both Iowa riverboats and racetracks. But Senate Republican Leader Stewart Iverson of Dows says he fears new lawsuits over Iowa’s tax code are just around the corner.Iverson says he could claim every tax is discriminatory since some folks get taxed more than others, and he asks “Who’s going to write the tax code for the state of Iowa — the Legislature or Iowa supreme court?” Iverson says he’s heard some groups are considering a challenge to sales-tax exemptions for farmers, or the state’s pickup-truck registration fee, which is lower than the fee for cars.