Not Legal Advice: Each state has its own laws regarding diving board installation and use in private pools, though none appear to have made them illegal. Many insurance companies refuse to place coverage on a home that features a pool with a diving board.
FINA Guidelines state that a minimum pool depth of 11.5 feet is required for a one meter diving board. Some states set limits on pool depth that is too shallow to allow for a diving board to be installed and safely used.
Of interest, some members of Congress are currently pushing for a mandate that would insist that all community pools would need to install a lift system to help the disabled into the water.