Guinan v. United States

Over five years, the Guinans (plaintiffs) split time between homes in Wisconsin, Georgia, and Arizona, spending a majority of the five years' time in Wisconsin during only one year; while the Wisconsin house was their largest, they held driver's licenses, voted, and filed state tax returns only in Georgia and Arizona, once even declaring the Arizona house their principal residence to satisfy a now-repealed statute. After selling the Wisconsin house and paying tax on the roughly $45,000 gain, the Guinans sued for a refund, arguing the sale should have qualified for the tax exclusion available for a principal residence held at least five years; both sides moved for summary judgment.