City and Owner Share Maintenance Duty for "Special Use" of Sidewalk

Facts: A pedestrian was injured when he fell through a concrete-filled metal grate in a public sidewalk. The grate covered a defunct stairwell to the basement of a building on the property abutting the sidewalk. The stairwell had been reconstructed with the grate by the abutting property's owner in 1968 in accordance with city specifications. Before the reconstruction, it had been installed solely for the abutting owner's convenience.