It's a serious problem for thousands of California couples: as soon as they travel out of state, their marriages may no longer be recognized.
That could spell disaster if one of them winds up in a hospital while on vacation, or if a family needs to move to take a new job. Californians may find themselves unable to make medical decisions for each other, or could find themselves with no legal custody over their children.
He admitted that he might be overruled by a court. The governor of the state, Susana Martinez, opposes King's opinion, and expressed her wish to withhold legal protections from out-of-state couples.
In fact, members of the state's Republican party want to go even further, and are pursuing a plan that would allow the state to pick and choose which marriages it has to recognize.
Several other states have the same problem: couples from Massachusetts, Connecticut, Iowa, New Hampshire, and Washington DC all could see their marriages disregarded as soon as they cross state lines.