SACRAMENTO — State GOP lawmakers and an anti-tax group made a novel request of the Third District Court of Appeal on Tuesday when they asked justices to block a $9.3 billion tax-hike proposal that the governor has vowed to veto.

Republicans and members of the Howard Jarvis Taxpayers Association sued the Legislature, the governor and more than a dozen other state officials to stop the Democrats’ plan to enact a 39-cents-a-gallon fee on gasoline, an income tax surcharge and a 3/4-cent hike in the state sales tax. Democrats passed the complex deficit-cutting package on Dec. 18, arguing that because the tax increases are “revenue neutral” — the new gas fee partially replaces an existing sales and excise tax, for instance — they require approval from just a simple majority of legislators. The fees did not receive a single GOP vote.