Donald Trump says he cannot release his tax returns because he is undergoing an audit that goes back “four or five years.” But the Internal Revenue Service usually does not look back more than three years. “Generally, the IRS can include returns filed within the last three years in an audit,” the agency’s website says. “Additional years can be added if a substantial error is identified.” The IRS further reports, “The statute of limitations limits the time allowed to assess additional tax. The statute of limitations is generally three years after a return is due or was filed, whichever is...