From 1979 to 1984, he paid $4,299 in Michigan income taxes on his federal retirement benefits. At the time, Michigan exempted its own retirement benefits from taxation. However, pensions paid by the federal government, other states, and private industry were only entitled to a $7,500 deduction. In Memphis Bank & Trust Co. v. Garner (1983), the Supreme Court held that states could not levy franchise taxes on federal bond interest if they exempted their own state bonds from taxation. Upon learning of the decision, Davis filed amended Michigan tax returns to 1979, claiming tax refunds on his federal retirement benefits. The Michigan Commissioner of Revenue, the Michigan Court of Claims, and the Michigan Court of Appeals ruled that Davis was not entitled to a refund. The Michigan courts ruled that he was not covered by the nondiscrimination provisions of , as he was retired and therefore no longer a federal employee. Davis appealed to the U.S. Supreme Court. In a rare occurrence, Davis argued his own case pro se before the Supreme Court. Although state attorneys general often argue their own cases when they are sued in an official capacity, it is unusual for private parties to appear pro se at oral arguments. Davis divided his time with Michael K. Kellogg from the Solicitor General's office, who appeared for the United States as amicus curiae. Opinion of the Court The Supreme Court ruled 8-1 in favor of Davis. The majority opinion, written by Justice Anthony Kennedy, held that states could not tax federal retirement benefits if they exempted their own state retirement benefits from taxation. Since retirement benefits were earned by employees as deferred compensation, federal pensions are entitled to the nondiscrimination provisions of , which covered "pay or compensation." The state of Michigan could remedy its discriminatory taxation by either removing the tax on federal pensions or levying a tax on its own pensions. In a lone dissenting opinion, Justice John Paul Stevens argued that the tax was not discriminatory because it treated federal employees the same as other Michigan taxpayers. Since most Michigan taxpayers did not receive retirement benefits from the state, they were also subject to the Michigan income tax. Aftermath Michigan chose to extend the income tax exemption to federal retirement benefits. Davis received $4,299 of tax refunds. Fourteen states that exempted their own state pensions from taxation had to refund billions of dollars to federal