His summons for jury duty suggests, based on Ohio policy for selecting jurors, that James has likely maintained his voter registration, or driver's license, or both, in Ohio since "taking his talents to South Beach" in July of 2010, over three years ago.
Actually, we can drop the "likely" qualification: a search of registered voters at the Ohio Secretary of State's website (type in LeBron James and Summit County) indicates that he is still registered to vote there.
James should have surrendered his Ohio driver's license and obtained a Florida driver's license within 30 days of establishing FL residency in 2010, according to this Florida DMV document (see Section 2.3 on Page 8 of the document / Page 9 of the PDF, and pay attention to criteria (d) and (e) there). While James still owns property in Ohio, he spends at least nine months per year with his fiancee and children in his $9 million house in suburban Miami, and he is employed by a Florida business entity, viz. the Heat. Particularly in light of Florida's lack of state income tax, it is likely that James has taken every step to establish Florida residency.
Hopefully James is not so brazen as to vote in two states, so let us assume that he is registered to vote in only Ohio, and that he has voted by absentee ballot in 2010 and 2012. Is it possible that Florida considers the King a resident for driver's license and tax purposes while Ohio accepts him as a resident for voting purposes? Ohio's voter registration form defines residency as "the location that you consider to be a permanent, not a temporary, residence . . . the place in which your habitation is fixed and to which, whenever you are absent, you intend to return." That is a heck of a mouthful, but a clever barrister could argue that James considers Miami to be only a temporary residence, and he still intends to eventually return to the Akron area when his pro hoops days are done. James's Family Foundation, which focuses on needy youths in the Akron area, suggests he has enduring ties to the Buckeye State.
Alternatively, James may have registered to vote in Florida after moving with his family there following "The Decision." In such case, James should have filed a request to cancel his Ohio voter registration. Perhaps James neglected to cancel his Ohio voter registration as he should have; under this scenario, when he received the Summit County, OH jury duty notice at his Akron house, rather than protest it based on his Florida residency, which would be entirely legitimate, he decided to acquiesce out of a mix of civic pride and public relations concern.
Still, while residency is not clearly defined and is not necessarily consistent under state and federal law, it cannot be denied that James's appearance for Ohio jury duty undermines any claim he may assert to Florida residency for tax and other purposes.