MADISON, Wis. – A tax expert cautioned against reading anything negative into the paltry 2017 state tax payments by U.S. Senator Ron Johnson – less than 0.5% of his income. Andrew Reschovsky, a retired economics prof at the University of Wisconsin-Madison, who specializes in taxes, said there could be many explanations. These, he said, include business losses, a special one-year deduction, even a large charitable contribution. Reschovsky was contacted about Johnson’s taxes after the Milwaukee Journal Sentinel found relatively token 2017 state tax payments. Reschovsky said he had no particular knowledge about Johnson’s situation. “There are a number of ways in which one can reduce your Wisconsin income tax liability perfectly legally,” he said. Meanwhile, Johnson has declined to release his 2017 federal tax documents that form the basis state tax calculations. Johnson’s staff, when asked, has been dismissive without clear explanations.