ALBANY, N.Y. — New York’s top court on Thursday rejected damages claims against state inspectors who continually recertified a tour boat for 48-passenger capacity before it overturned in 2005, drowning 20 people on a fall foliage tour.

The Court of Appeals unanimously ruled that the state generally isn’t liable for ‘‘the negligent performance’’ of government functions unless it has some ‘‘special duty’’ to those hurt.